After the Musk acquisition, the identity politics ultras quickly moved to mastodon and bluesky. Regular people were slower to move if at all because of switching friction.
Social media is an amplifier: most of the users are passive consumers or retweeters, and only a smaller minority drive the conversation.
Traditional media also loves to get stories from social media in order to "get the pulse" of society and because journalists are lazy and desperate for narratives. A relatively small social movement can therefore use social media to catapult its message onto traditional media and thus onto society at large.
By isolating themselves from the amplifier, the identity politics ultras were no longer able to push their political message (and witch hunts) to such a large audience, the message stayed confined in spaces that were basically invisible to the average person, and the message faded away.
Yes it wasn't just because of the Musk purchase, but it was definitely a factor.
You don't seriously believe that was because of the Twitter purchase and not due to a coinciding social shift, do you?