I don't think legality has much of an influence on it to be honest.
And IMO if it were regulated, and your average source was a smoke shop, or (and presumably not so well grown, etc) a corner shop, or even pharmacy, chances are you could do a better job of keeping it out of the hands of small children, I do think its probably not such a great idea for still-developing kids to be blazing up. That said, never seemed to do me any harm.)
But at least if there is some sort of structure in place by which to legally buy it, we cut down on the availability to the very young, as if its legal, the large grow ops can always undercut the street dealers. Although I'd certainly legalize (not decriminalize, legalize, so its SEEN to be as respectable as opening a 6 pack of cold beer)
It isn't a war that can be won by simply arresting people. People have been trying with all manner of substances since the original racist campaign against it by one harry anslinger, of the US, a scumbag of pretty unpleasant proportions, who characterized it as the favourite of dirty, slovenly, rapist, thieving workshy mexicans and demonized it, claiming it made people violent, prone to sexual misconduct of various stripes at the nastiest end of the spectrum. Which as we now know is utter horse shit. Its certainly a lot less harmful than alcohol and tobacco I think it can be fairly said. Just think how many hospital trips would be saved by people who didn't have a broken bottle or a pint glass smashed in their faces on a friday night by some drunken thug. Anyone been in hospital on a late friday night and seen the waiting room in the ER? its not pretty. I'd sooner have a bit of red-eye than half a broken bottle of stella sticking out of them:P
Not to mention if its fully legalized, as it should be, distributed properly, there is money from (and hopefully not excessive) taxation, badly needed to fund things like hospitals, psych counselling for people of any kind, no matter the cause, those services as I understand it here are badly under-funded, money taken away from the filth that would otherwise be used to persecute growers and consumers could be better spent on catching violent thugs, sexual attackers, paedophiles and as for the argument that a lot of the money stream associated with drugs (of any kind) is going into the hands of terrorist organizations, why NOT yank that particular carpet from under their feet? by keeping other substances than alcohol, tobacco and caffeine illegal we are admitting that we would sooner fund terrorist organizations, and put non-violent 'offenders' in prison, and destroy families in the process, and the govt. is happy to ignore its own specialist advisors on psychoactives, whenever their scientifically thought out advice conflicts with the official agenda. Meaning we essentially have them there as a token, and smoke and mirrors to take attention away from the fact that we are still officially fighting a 'war on drugs', pushed by the US that simply isn't something that CAN be won in that way. There is only one way it can be won, and that is by the pro-legalization side. Because there will always be a demand.
That alone, means it isn't going away. Where there is demand, there is supply. The only question is, how do we manage that in the way that results in the least harm to both society, families, and individuals.
Take, for an example of recent and outright nasty harm done by govt. legislation banning supply of, for example synthetic cannabinoids.
'spice' type products. I've kept track since they first came out and could be bought either online or through head shops. And at first, the synthetics were relatively benign, the likes of CP-55,940, JWH-series compounds, and where in the indole type compounds the indole nitrogen was fluorinated to provide an extra potency, it was invariably a 5-fluoropentyl group. It so happens that is relatively safe. But eventually, after banning, compounds were dug out to replace them that got progressively nastier and nastier, to the point where changes were made such as from indole to indazole, which seemed to massively reduce the duration of action, making them more reinforcing, super-potent compounds were brought out that were outright scary. One of them lasting about 15 minutes, maybe 20, capable of causing seizures, a highly potent, full agonist (THC is a moderately efficacious partial CB1 agonist, CB1 being the primary psychoactive cannabinoid receptor, CB2 being primarily concerned as I understand it with immunoregulation and regulation of inflammatory processes) and using a 1mg/1ml solution, I estimated that an active and potent dose of this particular synthetic cannabinoid, which was widespread at the time, after a wave of bannings, not only induced a very rapid tolerance, far more than weed ever COULD even if you tried, and within maybe the second day of use in a row tachyphylaxis would also kick in. And estimated as best I could by dilution and carefully measuring, that an active dose of the drug itself must have been within the region of <25ug. That is SIGNIFICANTLY more potent than fentanyl, the synthetic opioid (which for comparison is around 90-100x as potent as morphine on a weight basis)
And trying the 1mg/1ml solution made up with glycerine and propylene glycol to be usable in an e-cig, maybe 4-5 tokes was enough to hit like a tank. Now I could see this stuff being useful in an inhaled form as an ultra-rapid acting (seconds in onset, inhalational route) antinauseant and anti-vomiting agent for those with cancer chemo-associated nausea so they could last long enough to get their oral medication down and working. But for that stuff to turn up sprayed on carrier material of uncertain accuracy as to stated concentration, intended for smoking in a bong, was to be honest, scary.
And to work directly with the stuff, not in solution or on a substrate you had to be as careful with it as you would with raw fentanyl HCl. One slip and unlike fent, you'd not as likely end up dead, but certainly out cold. Cross-contamination of someone making a diluted product with someone else through a nick in gloves, or an invisible speck of powder getting on the skin, chances are the recipient would hit the deck in short order.
Then when they were really really forced, by govt legislation to scrape the bottom of the barrel, 1-(5-fluoropentyl) substutition changed to 1-(4-fluorobutyl) in many cases. Which is a damned dangerous product, because it turns out that aliphatic hydrocarbon chains of an even number of carbons with a terminal alkyl fluoride get metabolized via beta-oxidation to (mono)fluoroacetic acid (di- and trifluoroacetate are not similar toxicologically speaking) but this is a deadly and cumulatively toxic metabolic poison, it works by being metabolized, like acetate does to citrate, fluoroacetate does to fluorocitrate, in the Kreb's cycle, vital for mitochondria to produce ATP. And whilst the mechanics are different, the result is something like cyanide and azide (although these block cytochrome C oxidase) but both interfere with mitochondrial energy production and starve the tissues of energy on the cellular level. Thus targeting the most, those tissues with the highest energy requirements that need the most ATP to function (ATP, adenosine triphosphate is the cellular 'currency' unit of energy), this means the brain, the heart, and reproductive organs especially hard hit by toxins like this, as well as the nervous system.
And fluoroacetate poisoning is almost untreatable, and its extremely poisonous stuff, grazing of a couple of plants that produce it, some in australia and some in south africa, are well known as being able to kill lifestock, and the carcasses that get scavenged by such creatures as feed that way kill them too. Toxicity wise, its easily on a par with some of the middling-level organophosphate nerve agents. I got a head shop to take certain products off the shelves after I found those particular changes had been made, warned them and told them exactly what the problem and the poison was. At least one place got rid of them because of that, thankfully)
Plus a couple more synthetics appeared, cannabinoids, that whilst it wasn't their cannabinoid activity, that was the problem, but something unknown at least to me currently, but IIRC, something with a dimethylated valine (one of the basic aminoacids that is used in protein synthesis, perhaps that had something to do with it, or maybe pyruvate kinase inhibition, if I were to guess at possible suspects) caused waves and waves of deaths over in eastern europe and some on the continent too.
All because of progressive thoughtless legislation. And it hasn't stopped much being available, things can still be bought on the dark web.
Forcing such a trade as the psychoactive trade underground isn't going to help, its going to create danger where there was little, more danger where there was a modest amount, and then things will go progressively downhill from there.
Or for a more classic example, take making sassafras oil hard to obtain, which is used for the recovery of safrole, a methylenedioxypropenylbenzene that makes for an excellent precursor to (via bromosafrole/iodosafrole etc) MDMA via a number of routes that are generic for taking a propenylbenzene to the corresponding amphetamine. When this oil became highly watched, all it served to do was drive prices for genuine oil through the roof, and lead to substitutions being made that would provide not the methylenedioxypropenylbenzene but the likes of para-methoxy, resulting in the extremely dangerous PMA, or PMMA (para-methoxyamphetamine, and the corresponding 4-methoxy-methamphetamine respectively) via unwatched and much cheaper oils such as apiol from parsley seed oil (the essential oils of a large number of spices yield interesting propenylbenzenes or allylbenzenes that can be isomerized to the propenylbenzene and produce what Alexander Shulgin, rest his soul, termed 'the essential amphetamines', those coming from widely available kitchen spices and the plants that provide them, isolated via distillation and then treated with the same kinds of reaction system that would turn safrole into MDMA. It just happens that 4-monosubstituted amphetamines are for the vast part, iffy as fuck. PMA and PMMA are MAO(a) inhibitors as well as serotonin/noradrenaline/dopamine releaser/reuptake inhibitors which is a potentially and in these cases likely lethal combination, PMA is like MDMA in many respects regarding its effects, but with a TINY region between effects and fatality. I've never had it, and the only reason I'd have anything to do with it is as a cheaper substrate to practice a reaction scheme on to be used for something else, I'd not take the product, I'd not sell it, in fact I'd destroy it immediately after identification and confirmation of success. But most people aren't LIKE me in that respect, most of them want an easily available, cheap substrate to knock out a 'bargain' basement entactogen, and hell take the consequences and the people who use it.