There is also !internetisbeautiful@feddit.de

I signed into my dataterm.digital account but when I go on profile I see my feddit.de profile even though I didn't login with it.

Ok so in my case from your possible reasons it can only be a delay in synchronisation because dataterm.digital is not disabling downvotes and is also not defederated from lemmy.world and vice versa.

But it's still still weird and a bit confusing.