Fair enough. I've heard 'abolish the police' and 'all cops are bastards' (whatever that means) too, so such a sentiment definitely exists. Either way, those usually espousing such things don't seem to have much of a concrete plan in mind (and don't have to, because offering concrete solutions isn't the purpose of such rhetoric).
> According to the New York Times, the slogan and movement failed to result in any meaningful policy change. This was attributed to the slogan having no clear definition of its goals.
> I've heard [...] 'all cops are bastards' (whatever that means) too
Is that an honest question?
Usually it asserts that police institutions operate similar to organized crime, where some level of bad acts (e.g. perjury, evidence tampering, abuse of power) are a de-facto requirement of continued membership. Thus the corollary that anyone who survived there long-enough to be "a cop" must have become "a bastard" to do so.
Compare to: "All mafia members are bastards."
Such systems are self-sustaining because each cohort has the dilemma of defending itself against being denounced by the next. Forcing incoming members to commit the same crimes means they are "stuck in the same boat" , changing incentives from "reveal their crime" to "hide our crime."
To add to your point: sometimes people point to the videos catching cops abusing their power and say “it’s just a few bad apples.” They’ve been saying it for decades. It turns out that is correct as the full saying is “a few bad apples spoil the bunch”. Police departments don’t get rid of the bad apples, the bunch is spoiled and rotten. So far gone that the few good cops who join and speak up are railroaded out. Look at the Los Angeles CA police where there are different gangs within the police department.
> According to the New York Times, the slogan and movement failed to result in any meaningful policy change. This was attributed to the slogan having no clear definition of its goals.
(from the Wikipedia page you linked to)