If you think buying a house and renting it out "manipulates economic conditions" you need to prove it because that's a claim, especially with regard to "manipulate."
Maybe it is (I'm not so sure but I'm open to the argument), but even if true, it's a completely separate thing from someone buying a home and renting it out.
The homevoter hypothesis is mostly nonsense. There isn't a coordinated, conscious effort to restrict the supply of homes based on rational expectations of excess returns. People restrict the supply of homes due to misguided aesthetic reflexes, racism, nostalgia, and a bunch of other stuff, not because they are mustache-twirling capitalists.