Indeed! By what definition are humans "self-aware"? How do I know everyone else but me is self-aware or just well-programmed automatons that act as though they have the same kinds of experiences as me?
You have to wonder if there's some 1-5% of humans who don't meet the bar of being self aware. They seem to exist as parodies of people who can't learn or reflect on past actions. Being on a continuum would make a lot of sense with the sharpest crows and dullest people maybe crossing over a bit.