They tried banning landlords in specific neighborhoods in Rotterdam.

It lead to gentrification.

The people who bought the units, on average, were more wealthy than existing renters, but less wealthy than existing owner-occupiers. Basically, it forced poor people out of that neighborhood, and replaced them with middle class people.

There’s a lot of reasons why buying a house is expensive. In many places, it’s less because of corporate landlords, and more due to population growth outpacing housing growth.