Is it possible that this guy was 100% invisible???
absolutely, it's really not *that* hard if you know what you are doing.
And there's different levels of anonymity - hiding from the general public is easy, while hiding from the NSA might be a lot harder. He only needed to do the former to keep his name unknown, though he probably attempted the latter too.
anyway, OP's post is some kind of nonsense / pure speculation until proven otherwise. The only relevant fact is being a renowned cryptographer. Actually being 38yrs counts as negative evidence to me, since it's so very unlikely Satoshi would have used a pseudonym yet also given his real age.