Anecdotal, but reddit is REALLY cracking down on users regarding the protests related to the US/North America tariffs. There is a very murky line as to what reddit corporate wants people to say and not say regarding the protests people are organizing on corporate owned social media because sure.
Same with the inevitable pushback against blocking twitter.
That said: I sincerely doubt it will go anywhere. It took YEARS for people to leave twitter and that was only because a different corporate owned social media, bluesky, had open sign-ups. There is no alternative to reddit.
So we might see a small burst of newbies on lemmy. They'll likely get driven away by the usual suspects.