My guess is that as the need for housing has increased (population growth, short term rentals taking up supply, etc), we haven’t been building the right kind of homes to fill the void.

Nobody is out there using land to build “starter homes”. It’s either large, expensive houses or apartment complexes, so the demand for home ownership is high, but the ones available to buy aren’t cheap.

It would be like if nobody made affordable cars, so most drivers were stuck either leasing or saving up for a Lamborghini. (Hyperbole, but you get the idea)