If you were offline and missed it, Media Matters has a rundown of what happened. But the tl;dr version is that Musk is big mad because ADL has repeatedly pointed out that since Musk’s purchase of Twitter (I refuse to call it X), antisemitism on the platform has increased. Now, ADL is hardly the only organization to show this in its research, but ADL is a well-resourced, longstanding institution with a lengthy record of corporate accountability wins.
As a psychologist, I believe the ability of Facebook and others to target "highly suggestible" people with inflammatory content will almost certainly lead to more and more violence that will be nearly impossible to predict or control. Many of those targeted by the "engagement" algorithm are likely to be unstable loners with access to automatic weapons and a general inability to separate truth from emotionally compelling falsehoods. They will be made to feel a sense of urgency and some will respond with violent actions. Until social media companies are held accountable via civil liability this will continue to be our fate. These "products" are destroying society and will only grow more powerful as they gain more knowledge about users. We're in real trouble here people. The zombie army is on the rise.