Three reasons. One you know and that is money from his base. The other is to lay the groundwork for a fascist takeover of media companies when/if he gets back into office (or some like Ron DeSantis). Authoritarian figures hate free press and through extension any thing like Facebook or Twitter that does not bend to their will. If they come back into power in 2024 we could see these social media companies destroyed. The last is that they are easy targets on both the left and the right so why not pick a frivolous fight with them to stay in the spotlight.