Sane, good people who cannot afford to be in $WestCoastCity do not move into a tent and acquire meth habits. They move away, somewhere they can afford. I know, I’ve lived with these people, I’ve been these people. Sane-but-not-well-off people leaving is probably harmful for $WestCoastCity's culture and economy, but it is not where the blight comes from.
It’s drugs (see: San Fransicko) and crime-tolerant laws & attitudes.