The main reason they can't get housing though is that the government of California, which is dominated by Democrats, refuses to allow sufficient housing construction to make housing affordable.
Two exceptions (see https://en.m.wikipedia.org/wiki/List_of_mayors_of_the_50_lar... ): Dallas-Fort Worth and Oklahoma City.
Full disclosure: I don’t know much about them, and I doubt anyone in this thread cares enough to merit a deep dive. A little light googling suggests both struggle with homelessness (not surprising: both tend to have mild winters). DFW seems to take in essence the liberal approach: social services support with some encampment clearing and forced transport away from the city; OKC seems to be working on a rehousing program (how progressive of them) combined with faith-based charities and private/public partnerships.
For context I'm a center-left person, but at this point I'm pretty fed up with the standard California Democrat stance of simultaneously saying that housing affordability is really important but also using many tools of government to actually block housing construction.