I think cops are so afraid of becoming media fodder - suppose one of the little darlings hurt him/her/itself and blamed the cops? Since the police receive no support from city or other elected officials against the BLM/Antifa/college student whiner crowd, I think they are very reluctant to act. You need to have the political part of the city supporting them again, but in most cases, the politicians either want to ditch the cops at the first sign of trouble, or even spend their time actively demonizing them.
I think cops are UNION THUGS, working in league with their Democrat socialist master and Union bosses.