Yes that's true, extremists in any political faction share a lot of common characteristics, and de-legitimising their opponents is step one. Deplatforming is a significant concern for sure. That doesn't excuse it anyone though. What disappoints me, both of us probably, are those that argue vehemently that it's wrong when one group does it but give it a pass when it's done by their political allies on any side.
Evil clowns to the left, the Joker to the right, and I wish there was a middle to be stuck in.