e.g. https://www.dailymail.co.uk/news/article-8664345/Aggressive-...
https://twitter.com/i/status/1267283980514201610
https://twitter.com/i/status/1269043437275435016
Etc.
Maybe some of them knelt voluntarily. But what would have happened if they hadn't. To me at the time there seemed to be a lot of social pressure to "kneel" and accept the narrative and the will of the mob.