But the moderator AI does not need to understand the meme. Ideally, it should only care about texts violating the law.

I don't think you need to improve that much current LLM so they can detect actual harm threats or hate speech from any other type of communication. And I think those should be the only sort of banned speech.

And if facebook wants to impose additional censorship rules, then it should at least clearly list them, and make the moderator AI explain what are the violated rules, and give the possibility to appeal in case it is doing wrong.

Any other type of bot moderation should be unacceptable.