Honestly, do we need a legal definition of what "self hosting" is and what isn't?

I didn't see your post and in the modlog I can only see it's title: "Apparently I'm into Web3, says Netcup" [ed: Netcup is a hosting company].

If your post was discussing stuff specific to your hosting provider, then the mods did well in removing it - if you were talking about things that would have interested this community, then they have probably been too rash in removing the post.