It's certainly true that allowing in more people would impose a cost on the current residents. But you can't stop people from moving towards economic opportuni

It's certainly true that allowing in more people would impose a cost on the current residents. But you can't stop people from moving towards economic opportunity without putting up something like a border wall around SF. And also, how would you feel about rich people saying that they like having lots of money, and how are these poor people to demand that they give up money in taxes when that would degrade their quality of life? It's totally true that for rich people paying taxes will make them worse off. But that's to a lesser extent than the extent to which it will make poor people better off. So I don't think it's illegitimate for rich people to be forced by the electorate to pay taxes at a higher rate even if rich people don't want that. And I don't think it's illegitimate for California to force SF to build local housing for the people currently commuting 2 hours to jobs in the city even if that makes current residents a bit worse off.