Having done work as an EMT, people get violent on their own volition more often than you may think. Completely anecdotal but I've seen dozens of drunk/high/mentally ill etc people attack others and zero incidents where the cops escalated the situation.

It seems to me that cops/no cops each has its own pros and cons and neither is a clear "right" solution.

We definitely need more mental health support and less frivolous prosecution for things like drug possession and homelessness. Social programs would (hopefully) go a long way in addressing some of these at their root cause.