I do find some of content/language people use hilarious though. Especially the first one (Gilbert). I can’t figure out whether it's half a joke and they're trying to be funny, or if they seriously think it's an effective choice of words to convince people it isn't really for sale. I guess it is at least getting some extra attention because of it.
I think it would be more convincing to just say "Domain is not for sale", "Under Construction" or simply nothing at all.