How does abolishing rent control make millions homeless? The housing would still be there, just with richer people living in them? It would certainly increase commutes for the working class though
The housing would likely sit empty as richer people are a limited quantity market, and are not usually shopping for the typical quality of a rent-controlled or low-income unit. Meanwhile the working class folk you mention are sleeping in their cars in the city, because a 4 hour long commute one way from the exurbs is not feasible.