I don't visit ani.social, a quick glimpse just now shows me a few Images that seem like borderline, but not straight-up "drawn sexualized child characters". No idea how they usually are.

But from following the story, it seems pretty typical that even the lemmy.ml admins - who develop Lemmy as a whole - would do a defederation without a public transparent process or even a notification to the deferated instance. That's straight up unpolite.