The ads pay for the content you watch at the time. It doesn't pay for your right to dictate the terms of their service in perpetuity. Thus, this whole line of thinking is a non-starter. Further, YT is not required to support whatever business model you build on top of theirs unless they've agreed to a contract of some sort. Do you know of such a contract?

destroying shareholder value

Maybe so, but their rationale at the moment is that extremist videos create a hostile environment for their users. They would rather not perpetually expose their preferred users to the toxicity of extremism. It's arguably a move to increase shareholder value. If you think they're wrong, don't be a shareholder.