99 percent invisible had an interesting podcast on one approach to this issue. Apparently 40 years ago LA decided on a "Containment" plan for skid row downtown, basically locking it into a roughly 50 block area. It was interesting to hear how it happened and how it played out over the ensuing years up to now, and how it is under threat as the land is considered just too valuable.
https://99percentinvisible.org/episo...tainment-plan/