A cop and his boss acting badly may be systemic. It isn't structural.
I personally believe profiling is not the same as racism, both have clear definitions. Both also sweep up innocent people and lump them in with miscreants who "look like that" so it's not something to go to the mat over. I basically agree.
What I don't agree with is your over the top rhetoric.
"We've seen 400 years of structural anti-black racism here, with no end in sight. The USA has had more than 240 years to fix that."
This disregards John Brown, the civil war, the civil rights act, affirmative action and a multitude of programs policies and attempts to bring justice and some measure of equality of opportunity to the minority. It also ignores the widespread support of the current protests and paints America with an overly broad brush of racism. In short, it does exactly what racists are accused of doing. I realize you likely read this kind of thing in a book. That doesn't make it any better nor more fair or accurate.
When you say "structural" and attempt to equate profiling with slavery or segregation, both of which were structural in an attempt to imply we are exactly the same place legally and in terms of opportunity, and how the system treats minorities when we manifestly are not, it's offensive, inaccurate and it raise hackles.
I really didn't want to get deep into this, and I'm not debating, but I think this point needs to be raised because there is entirely too much hot and shallow speech about lately and it detracts from the core point.
Structural racism is often called systematic or institutional racism[0]. It doesn't have to be deliberate, but instead is something that perpetuates reduced status of a racial minority by the way laws or institutions are structured.
A commonly used example is the difference in laws and sentencing between crack and powered cocaine. The 1986 Anti-Drug Abuse Act created a mandatory minimum sentence on 5 years for 5 grams of crack cocaine, but the same Act made the 5 year minimum sentence apply to 500g of powered cocaine[1].
This doesn't appear to have been deliberately racist, and instead it was mostly in response to media hype about crack. But it had the result of meaning blacks were much more likely to be sentenced to prison for minor drug offences.
[0] https://en.wikipedia.org/wiki/Institutional_racism
[1] https://www.criminaldefenselawyer.com/resources/crack-vrs-po...
Unlike the average San Francisco resident I've actually spent a lot of time around blacks and black communities so this isn't theoretical one dimensional abstract signaling of the type that is unfortunately too common lately.
The issue is deep and not nearly as simple as one sided "structural racism social injustice". A lot of it comes down to culture and how people feel about proper behavior. Along with contempt for cultures that don't have the same values. And willingness to engage in violent behavior.
But I don't deny black Americans have a rough time with the police and I do think we should do something about that. Maybe that is what is meant by "structural" in which case I agree, no argument.
I'm not sure what to do about people not liking each others culture though. I expect the bigots are the ones missing out, but I don't know if we can legal that problem away.