>Because that is what the housing market does. Allocates valuable assets to those who pay the most. Nowhere on the tin does it also say that it promotes social mobility or equality. Maybe it should, but it certainly won't as long as there is the idea that it already does.
You've hit on the hard reality that neither political side in the US has been willing to squarely face. The housing crisis is not the result of housing policies (though as you say there is probably some marginal effect there). It is the entirely predictable result of unregulated capitalism. In an unregulated capitalist system (defined as a system without any regulation on the accumulation of wealth), income growth accelerates with increasing wealth, and all assets are increasingly owned by a smaller and smaller fraction of the population.
You've hit on the hard reality that neither political side in the US has been willing to squarely face. The housing crisis is not the result of housing policies (though as you say there is probably some marginal effect there). It is the entirely predictable result of unregulated capitalism. In an unregulated capitalist system (defined as a system without any regulation on the accumulation of wealth), income growth accelerates with increasing wealth, and all assets are increasingly owned by a smaller and smaller fraction of the population.