This is ridiculously oversimplified, because there is no real market in housing. It is illegal to build in all of the places people want to buy. The purchase of housing by hedge funds isn't a problem on its own, it's simply a symptom of the bigger problem of supply restrictions.

The funds themselves say in their financials that they view housing as profitable because of the various restrictions on supply in every desirable city. They explicitly say that if those restrictions were lifted they would not be able to make money in that business and they would exit.