I think the most important job of law enforcement in a rich area is excluding or discouraging the presence of poor, dysfunctional people. It's not like dentists and engineers are knocking over gas stations if the police aren't watching them all the time. That seems to be where San Francisco law enforcement really falls down on the job*; they're not acting as a filter.

And law enforcement absolutely does not work nearly as well on the poor. There's been a rash of mass shootings recently across the Southeast at high school or college (mostly hbcu) homecomings. There were heavy police presences at every one of those. In Montgomery, there were police units within 50 feet of where the shooting started, but it didn't stop at least a dozen people from blasting away at each other.

Every time the Southern Poverty Law Center** or someone wins a case preventing police from rousting undesirables, they make life a little worse for citizens.

* Along with ignoring actual crime

** Those jackasses at the SPLC are the reason we've got panhandlers in every median where I live, so I'm a little bitter.