I am surprised and disappointed at both this site and this author going here, but:
Elon Musk's X arguably revolutionized social media fact-checking by rolling out "community notes," which created a system to crowdsource diverse views on whether certain X posts were trustworthy or not.
1. Wasn't Musk. Wasn't Elon Musk's X either. "Birdwatch" was in place before Musk bought Twitter.
2. Therefore, if it did revolutionise fact-checking, that would be an item from the Twitter board who were clearly going in the right direction in the year before Musk bought them, and he immediately took them in the wrong direction.