I don't think that's being disputed. Both the USA and Russia had incredibly violent labor histories in the late 1800s and 1900s. The main difference is that in Russia, the workers+peasants organized and won, and in the US, they lost.

Either way this both-sidesing of violence makes no sense. You might as well demonize every just cause in history, or every person that defends themselves from an aggressor with that outlook.