At the bottom of this, the beginning, imho, was the deinstitutionalization of the mentally ill that began 40+ years ago.
People who could not function on their own, take their meds, keep themselves stable, were released to their families and into communities who were woefully unprepared to meet their needs on a voluntary, outpatient basis.
And, this continues today. People who would have been institutionalized for care are largely now left to voluntarily comply with the medications and treatment that could stabilize their lives.
Add to that the chronic substance abuse population and we have huge numbers of people who will likely never be able to comply with and meet the criteria for traditional housing of any kind.
They can’t cooperate with helpful others, engage with service providers, comply with rules/the external structure that could help them resolve living situations many find deplorable.
There are those who are houseless by choice, and happy about it, also many who have fallen into homeless but have the emotional and physical resources to accept help that is there and pull themselves out.
Then there is the housing shortage, the affordable housing issue, the lack of adequate federal subsidies for the low income, etc., all of which most impact those functioning at a high enough level to pull themselves up.
Such a complex issue, but the truth is that a huge proportion of the chronically homeless, in these encampments that rankle so many, are people who last century would have had full time caregivers.
All the services in the world cannot help those who don’t want help and/or can’t see that they need it.
There is no simple answer.