On one hand I feel like actually changing your answer to prior questions is a weird flex on resisting/protesting AI since your answer was already used and sold to others, you're just making the website worse to actually search for answers. On the other hand I wonder if how stackoverflow is handling this violates safe harbor requirements similar to the recent twitter court case. They want all the ability to own user content with none of the liability of owning that content.
I feel like actual protest is to just stop providing answers in general. But that not visible. Even better protest is to provide answers on various forums and discord groups but that's also not very visible.