Your own data disputes your own argument.
First - you've unfairly cherry-picked a statement. Here is the full context: "Even when officers report civilians have been compliant and no arrest was made, blacks are 21.2 percent more likely to endure some form of force in an interaction. Yet,
on the most extreme use of force – officer-involved shootings – we are unable to detect any racial differences in either the raw data or when accounting for controls."
So right there in the very same para as your 21% argument, you have the author indicating that for more extreme violence there is no difference in police treatment among races.
Literally he's saying that "Shootings of Black men due to racism is 'not a thing'"
Second - that in some instances police are actually more likely to 'lay hands on' African Americans, by 21% actually disproves the narrative that 'African Americans' are in prisons etc. mostly due to disproportionate violence by cops.
The data presented in the article in question shows that Blacks are 2.5x more likely to be 'shot' - which is 'extreme violence'.
From the research, this would suggest that African Americans are probably involved in crime or situations which 'getting shot' is the unfortunate outcome.
Even if you apply the '21% disparity' - which would be unfair because the research indicates that's only for 'low violence situations' - that still does not explain the 250% disparity among races. Not even close.
So yes - unfair policing exists, and it's a problem, but the much bigger problem seems to be the inherent amount of crime.
That's what the data is indicating:
+ No racial disparity in more violent situations
+ Racial disparity in less violent situations
+ Quite substantial differences in the amount of crime
That American cops are somewhat too aggressive is without doubt, that racist cops exist is without doubt, but the extent to which they are, and to the extent to which it's systematic or 'bad actors' and the extent to which affects actual criminal behaviour is in doubt. There is also no doubt there is deep social malaise in the African American community.
The 'popular narrative' seeks to lay the blame mostly on cops, which the data does not support, also, it seems to ignore the 'Elephant in the Room' subject of the vast amount of crime in the community, which is also unfair.
Most Americans want to improve the situation, I think that narratives that support the nuance reality are more helpful towards that end.