I don't really care what happens to mom-and-pop real estate speculators. I don't think targeting any kind of investor is going to do anything for housing affordability, but my real target in this subthread is the PE thing, because "target PE investors instead of rezoning" is a super common NIMBY argument.

As a matter of politics, we're not going to pass any legislation that disfavors mom-and-pop real estate speculators, so I don't really see what's to be gained in litigating. I think you'd be pretty surprised at the demographics of those small-time investors; a lot of them are decidedly middle class. They're not representative of the middle class; obviously, most middle-income earners don't own investment residential properties. But that's not the same thing as saying that middle-income earners aren't represented among real estate investors.