I did. If you list a room for rent in SF that looks nice and is competitively priced, you'll also have thousands of applications.
What do you think is the innovation here? He's offering housing in a market with no housing supply. Of course he has market fit.
It seems the steps here were: Be born in commune. Notice SF has a housing problem. Suggest building a commune in LA and SF. Get funded by YC.
Maybe it's like asking for a date with a very attractive person, where everyone thinks they can't possibly get the date, so nobody ever asks?