Homes are not affordable anywhere people want to live. There is no prop 13 in North Carolina, and people are being priced out of our area. Same is true in Montana.
Rents are not higher because prop 13, but taxes collected are lower. High rents and high cost of homes is a supply and demand problem. Move out to Adalanto or Victorville, CA and you can buy a nice house for under $400k. If you and a partner make $50k each, you can do it. That's is not unlike we did. We got priced out of California and had to move.
This is an anti prop 13 article with some numbers: https://projects.scpr.org/prop-13/stories/housing-shortage/
The best they can say is that Oakland has 3k undeveloped lots that could be houses. The claim is prop 13 allows them to hold onto what would otherwise be someone's purchased home. That wont even house 1% of Oakland. You could magically put houses there and the market price for housing wouldn't change.
Being angry with prop 13 feels like being angry at handicapped parking spaces being unused. If the spot were not only for handicapped people, you still wouldn't have found parking there because someone else would have already taken it.