As long as I found the Nazi disturbing, the "denialism" in Tianmen square massacre or gulag or Ussr stalin purge or Uyghurs genocide from the far-left ideology is as much disturbing as the same from the far-right one. Just because this instance seems leftish and anti-Nazi, it doesn't leverage itself to a better position.
Yeah extreme ideologies are bad, but instead of talking left vs right, which is pointless as you are trying to comp genocidal maniacs against eachother. They are all totalitarian evil, we put extra labels on so we can pick sides.
how about we consider why groups want control over your life. The left cares for society and group rights, the right cares for individual rights. I could argue the value of both, but we are overpopulated and the desires of the individual shouldn't be valued greater than that of a society, our environment, quality of life, right to health and security from violence and economic greed. Im not saying the left is good at what they do but at least they try to manage the mess instead of arrogantly assuming market forces, churches or the metaphysical can or will solve peoples unnecessary suffering.
Sorry just because you (or "we") would love to put labels to pick sides, it doesn't mean I belong to your described "labels" or "sides" because I treat far left and far right are the same. Maybe some political compasses can help. I don't take sides. I agreed with the problems you think. Maybe you can try to stop putting labels (or picking sides) so that it might help to provide for some perspective angles. Wish you the best