> I.e. a literal roof over their head, that they can’t be taken away with little notice by their landlord for reasons completely beyond their control.

Yeah. Before I bought my home four years ago, three of the last four landlords I'd had had promised long term stability, only to non-renew the lease after the first year (for "other" reasons: "Wife thought she'd like the country, we're moving back to the city", "We want a smaller mortgage payment on our primary home", We're going to renovate and sell"). It's a lot of fun moving a family every year. Especially when around here you also have to come up with first, last, security and other fees and can easily be looking at $10K+ just to move.