It would make a big difference to me. :) But it would not change supply.

I have an airbnb off my garage. It's a granny flat, a bed, a small bathroom and a kitchenette. A sink, but just a hot plate a fridge and no oven. It's not somewhere you'd want to live for a long time, in my opinion. But it's a great place to crash for a few days, have a cold breakfast, some oatmeal, reheat left overs, etc.

There's people like me who it helps live in SF and offset property taxes, price of the house, etc. Bad actors/bad markets/etc certainly do exist, but like all things it's complicated.