> If we think it's important to have such disparate classes living close together even in high cost of living areas, then great - maybe this is the best way to make that happen.

Yes. I think it's important to have disparate classes living together in a dense urban environment, rather than a homogeneity of wealth.

In fact, I believe that attention to this priority is one of the main reasons that NYC is the greatest city in the history of world civilization, versus the bland expanse of stripmalls, chain retail, and cultural drought that defines the American living experience in many other areas.