Yes, if you didn't understand my point: there are homeless people in every society, but most do not have as many as silicon valley because they pressure them into accepting the help necessary to restore their ability to make rational decisions. Rational people do not choose to live outside on the sidewalk like rats, people who are drug addicted and who have untreated mental illness do.
All it takes to be homeless is not being able to afford housing, drugs or mental illness are not required. You really think all it takes is "choosing" and housing will appear for you?
Also, drug consumption and mental disorders is very often a result of being homeless. Try having bad sleep in your comfortable home for a few days in a row and see how quickly your mental stability deteriorates and how many bad decisions you start to take (anyone who has insomnia periods will attest)
This is not substantiated by data or even a plausible theory. The kinds of mental disorders that lead to homelessness are not something you can "catch" from your environment.