The causes of high crime in SF are like layers. Gascon was only the top layer. "Bail reform" is a layer. "Compassionate" releases of criminals due to Covid was a layer. Prop 47 is a thick layer. There was another ballot proposition and a court decision forcing the release of felons due to "prison over-crowding". Getting someone into a long-term mental facility is very difficult. However, except for Gascon (who has a few equivalents in other counties), these are all statewide. Two big (IMO) decades-long factors that are somewhat unique to SF are the city's wide open welcome and subsidizing of "homelessness" (including needle "exchanges" for druggies that end up being free needles that become litter on sidewalks, gutters, parks, and playgrounds) (including taking over older small hotels, which become hell-hole-havens for druggies, mentally ill, and prostitutes m/f/??) and the decades of city hall hostility toward and hatred for police/sheriffs (SF is, by CA's constitution, a contiguous city and county). And, of course, SF is infested with victimology-activists (as is across-the-bridge, criminal-coddling and -sharing neighbor Oakland).
There probably are other big factors, but those are the biggies that came to my half-caffeinated mind.