Encouraging people to use X drives money into the hands of fascists.

Cross posting content isn't really encouraging people to use it.

If they want to make some principled stand against toxic social media, then have at it. This is pure pandering to a very specific group.

Twitter, before Elon, was the company that literally banned your account for sharing the hunter Biden laptop story. That story was purported to be a "conspiracy theory" but was actually true. And people were locked out of their account for sharing it. That is true fascism.