Peaceful protests are always fine by me. It's a hallmark of a free society.
Riots are a hallmark of anarchy. People who riot do nothing to solve the grievance over which they're rioting, especially if that grievance is a legitimate one. In the specific case of the George Floyd protests, I avoided the entire issue until the body cam footage was released. I watched the full clips from all three cops, and while I don't think it was right to pin him on the ground by the knee to the neck, he was clearly saying he couldn't breathe before they even put him on the ground...I believe that the autopsy revealed he died from a meth OD? Don't quote me on that, I haven't sourced it, heard it from a liberal friend of mine.
Regardless, I know Jiu-Jitsu and I'm sure they could have kept him there by torquing his elbow behind his back rather than kneeling on his neck. That's just what I'm seeing from the body cam footage.