The question is, how do you stop Capitalism from subverting Democracy and the Media to perpetuate itself? I think one can successfully argue that capitalism is a human-scale paperclip maximizer, but for capital.
> PS: if we wanted to, a democracy could simply make it illegal buy investment property insuring that everybody had somewhere to live. Freeing people from the burden of rent.
Only if the wealthy allow it. You don't have to look very hard to find dead-in-the-water concepts/projects that have the support of a large majority of Americans across the political spectrum, but are hated by the wealthy, and therefore their politician proxies. These tend to die despite public popularity - alas, that's the downside of representative democracy.