Maybe humans are allowed to own some maximum number of properties for the purposes of renting it out, and that number will decrease over time.

Maybe banks can own houses and rent them out at some capped amount.

Maybe the government can own houses and rent them out with the express purpose of "rent to own", with absolutely no intention of "earning a profit".

I don't have all the answers, but I think it's pretty clear that companies owning 40% of ALL residental homes in a city and making massive profit renting them out does not make housing affordable, and it does not allow people to have their basic human needs met. Therefore something needs to change.