There's also the issue that raising wages will not fix the problem if landlords capture the wage increase by raising the price of housing. It's all about buying power, the absolute numbers mean nothing.
The free market can't solve all of our problems, and even if it could housing in particular is too important to wait on supply and demand forces to fix everything. Moving has very high material/time/emotional costs and humans need uninterrupted housing to maintain a decent life.
Things do not just adjust themselves as in the theories, weaker people are just squeezed harder. When they can't be squeezed any more, things _may_ change - but when is that?
The working poor are a pretty good example of this.
It's one of the cases where the market is working as expected (low wages since the offer is high), but it doesn't really translate in benefit for (some of) the people involved.