You are correct here. The only keepers losing are people who do not actually know how to win.
I have played twice, and victory was trivial.
Yeah, winning is trivial - you just don't open the damn box. It can't get more trivial than that. (Although, you didn't say whether or not your opponent had proved themselves by winning as AI against others a few times?)
It's still worth thinking about though, because something about my model of humans is off.
I didn't expect so many people to lose. I just don't know how to update my model of people to one where there are so many people who could lose the AI box game. The only other major thing I can think of that persists to challenge my model in this way...
AI Box Experiment Update #3
Tuxedage (AI) vs Alexei (GK) - Gatekeeper Victory
Tuxedage (AI) vs Anonymous (GK) - Gatekeeper Victory
I have won a second game of AI box against a gatekeeper who wished to remain Anonymous.
This puts my AI Box Experiment record at 3 wins and 3 losses.