My bet for the real reason for this is that it has been widely reported that Twitter artificially boosts Elon's account specifically. Many people noticed when they did this that his posts showed up in their feeds despite them not following his account. I bet this led to a massive wave of people blocking his account (it's as easy to block as it is to mute). And this population of users eventually got big enough for him to notice, and he wants his posts in everyone's feeds again.