I think it's a lot more likely that Trump pushing outlandish/false/inflammatory claims starts the civil war, not the fact that some YouTube videos suddenly vanish.

If you can prevent the former by removing viral reach of the latter, isn't that a net win? It's sad that a private company has to do it, but one could argue that it's the morally correct thing to do, in this case.

These people are free to host their videos on Parler / Gab / etc, and broadcast this nonsense without the free mainstream reach.