The trick for the homeless problem is what nobody has tried yet....encampments far away from civilization.
In places like CA that would mean encampments far out in the desert with bare minimum amenities.
If they want to destroy themselves that is fine.
Keep them far away from civilization.
Methadone Produce Pickers Inc.
Our workers always show up.
Our workers never go on strike.
You're close. And what does one do with them when you get them there? How do you keep them focused upon doing something productive, learning a skill or taking responsibility for one's world?
It's doing the hard work of weed control and habitat restoration, with the opportunity to see native plant systems respond over a period of years. Whether it's hands on, fire management, application of herbicides, tilling, animal management, or predator control, it is the satisfactions and frustrations of the feedback that matter. It is the relationships that develop that matter. The most therapeutic thing of it is the quiet.