There are also some interesting incentives that go the other way. By getting the big property managers involved, tenants or regulators that are upset by how thi

There are also some interesting incentives that go the other way. By getting the big property managers involved, tenants or regulators that are upset by how things are going have a new target for their wrath that: - is making money from the deal (unlike landlords now) - unequivocally knows the subletting is going on (unlike landlords now) - has an explicit contractual responsibility to aggrieved tenants (unlike AirBnB or other tenants) - has a lot of money that can be taken away if they lose a lawsuit (unlike other tenants), and - has valuable unmovable property located in the jurisdictions where the harm is being done (unlike other tenants and AirBnB). I'm not really sure whether these issues outweigh the points you made or not, but if this happens, it probably makes legal action against bad actors using AirBnB much easier.