Which is the fundamental problem with the whole YIMBY business: solving California's housing crisis requires dense housing, which is much more severely affected by what other homeowners and land-owners do than low density housing with large plots. The only way to avoid loud music blaring from the neighbouring units all day and night, or someone building a wall right in front of all your windows and removing all daylight, or an art gallery setting up shop across the street with an endless stream of visitors looking right into your home, or any of the endless other possible issues is through collective control over what others do with their property. Making everyone personally own the land needed to stop this happening is so inefficient that anything denser than American-style suburbs is impossible.

So long as this idea is a a fundamental plank of YIMBY-ism, all of the pretty claims about how high-density living doesn't have to be a dystopian hellscape are literally worthless, because every one of them relies totally on things outside the residents' control that the YIMBYs will be first in line to try and destroy.

That is the case in California. If you own property zoned residential and apply for a fully compliant building permit then it will almost always be approved (although fees may be high). Developers and property owners generally only run into long delays and battles with neighbors when they request variances or zoning changes.