Unless I’m wrong and SF is actually cheaper to rent always.
Even considering all this, it’s often only a small difference. And renting gives you a different and sometimes advantageous quality of life.
If you include historic price appreciation over certain periods, you can end up ahead owning, but nothing guarantees that same price appreciation going forward.
For non-rent control places new landlords subsidize the cost. It's happening a lot in Toronto right now. Tons of new condos that investors bought where the rent doesn't cover the monthly carrying costs. They are betting that price appreciation will make them whole (and more). That's a risky bet.
For rent controlled apartments, you basically pay based on what the tenant's rent is. So if you have someone paying 50% of market rate, that dramatically bring the value of the house down. I was renting in a 3 unit building that would be worth $6M empty, but with 3 tenants paying below-market rates, it was sold for about $2M.