That will never happen. Rich and middle class people don't tollerate poor households next to them very well since most poor homes are considered a "blight" on the neighborhood. They tend to form HOA's to boot them out.
That's exactly what's happening in gentrified area, have seen it in my city and it's evidenced in the video with refurbished buildings right next to ones that aren't, and refurbished streets on one block next with un-refurbished when turning the corner, and people of every color walking all of those streets. A great deal of refurbishment occurring in urban areas is in buildings which were boarded up an unused. The video doesn't necessarily tell that part of the story though.
we can have a walmart next door to an artisan hipster bakery.
That doesn't even make sense. What that describes is typical middle class suburbia with a mixture of upper middle, middle middle, and lower middle, and every race fitting into those sections. The walmarts and dollar trees are in fact near trendy eateries and fancy salons, and can shop at the cheapest grocery store in the city a quarter mile from the most expensive. Pawn shops and flea markets next to large shopping malls, mansions and cheap apartment, whatever, it's a huge mix these days, a huge wonderful mixture of stuff and people. Know what it's like to live in places without diversity; those places suck, and frankly love it here. Though maybe you're right and whites should stay out of the ghetto and just let it rot.
