Why do you understand? Why would you care how many people live next door?

There are potential negatives, sure. Like noise or making a mess outside. But those are already covered by other ordinances, so just enforce those.

As a homeowner with a family, I wouldn't care if there are 50 people stuffed living in the house next door. As long as they're quiet and don't make a mess, it's none of my business.

But if they did, they would probably come here and reply that they don't want 8 drunken college bros constantly partying next to their house either.

Personal I live in a SFH, and I have a family. Even though I don't want 8 drunken bros living next to me, they have as much right to exist as my rather loud and surely annoying toddler has.

I'd like for people expressing these political preferences to not be allowed to live in my neighbourhood either, but unlike you, I also recognize that you have as much right to live there as those 8 college students.

If foreigners could vote in San Francisco, the majority of which are renters, it would overwhelmingly crush this position.

3 college students could just about as easily be bad neighbors as 8.

Unless the idea is that 3 students would be too poor to live in that neighborhood, in which case a rule like that is even worse than I thought.