I was receptive to your argument up until you mentioned the "Ferguson effect".
The people of Ferguson Missouri were exploited by their policemen years before Garner was killed [1]. The Department of Justice found that the city itself had targeted African Americans, fining them at every turn, and imprisoning them when they couldn't pay. I find it hard to believe that these victims wanted to give their “protectors” even more money.
Frankly, pretending the anger isn't real, that it's just a few professional rabble-rousers riling up the woefully ignorant-- is akin to the rhetoric China has weaponized in Hong Kong.
It's not honest at all.
[1] https://en.wikipedia.org/wiki/Ferguson_effect
[2] https://www.stltoday.com/news/local/crime-and-courts/doj-fin...