This is hyperbole.
You know what happened to the longshoremen unions that organized to facilitate crimes by their members? That's right, they were declared as a criminal enterprise under RICO and every single member of the union was guilty of a crime.
SF has a cognitive dissonance right now: it doesn't want crime, but it doesn't want to punish criminals, so when criminals come uninvited, SF can't decide what to do.
Also, career criminals very rarely use violence to resist arrest. That is something that inexperienced or impulse criminals do. Any career criminal knows that using violence against the police will end up in a worse outcome than getting caught.
I would be interested to see a story where a criminal, in the comission of a crime, initiated deadly force against a policeman and was painted as a saint after their death or injury, leading to riots. This happens almost every day and no one cares about it.
They will have to wait for a violent event to happen first before doing anything.
Police is safe, SF voters get what they vote for, and thieves get goods. Win win win.
Lots of unions try the same and are far less effective; police unions are not inherently powerful, they are granted power by the fact that the citizenry in the US worships military and paramilitary forces and grants undue deference to them, particularly, in regard to this issue, in selecting the civilian political leaders to whom police are nominally accountable.