Yeah, that is big one. Perhaps we need to rethink housing. Shared restrooms, bathrooms, and kitchens. Keep the same restrooms on every floor. A gym with individual showers and a food court on specific floors.
Except this goes against American individualism on every front. Americans really only fit one sort of mold in terms of what they want: single family home, owned outright (usually mortgaged though). You can extrapolate that out to cities as well: young urban professionals pine for polished condos or lofts with nice views and located in trendy neighborhoods, but their "unit" is still theirs totally, with no shared primary amenities (by that I mean kitchens and bathrooms, not features like pools or gyms).
It just so happens that America is luckily predisposed to this kind of living, with an abundance of space to accommodate lots of people in their own non-shared living spaces. The problem with that though is that you limit the opportunities for business, because space is cheap, so you have to implement regulations and zoning to create opportunities for moneymaking and before you know it you can't actually build housing anymore, despite the abundance of space sitting right there.
What will distinguish these structures from slums in 10 or 20 years?