If Tumblr doesn’t go too extreme in any of these directions, I can accept federation with them. My main gripe with interacting with corporations is that they likely want to dictate the rules of the Fediverse.

So I can tell you Tumblr's policies are a copy of Instagram. It is even more conservative than gram. It doesn't want any nudity or porn or even bikini pictures. Sees a nip through a shirt, gets shadow banned. They outright ban users for it. But their bots can't handle porn bots. So average casual user/blogger will banned while porn bots proliferate.