Obviously anyone replaceable has a bad position to bargain, so it becomes a question of how replaceable YouTubers are. Clearly there are plenty of people who want to fill that role, but I don't know how the average user interacts with YouTube.

For me, if the creators I watch were striking and trying to force change, I'm not going to bother going on YouTube. I have no idea if "watching a specific set of creators" is a significant enough part of the user-base to really hurt YouTube enough to comply, or if most people would just watch other videos.