I think it would be Horizon Zero Dawn. I have not played it, but seeing as how new AAA IPs seem to get a lot of awards, I'm willing to bet it would get the most GOTY awards. If we look back at The Last of Us, it had the most GOTY awards of any game until it was dethroned by Witcher 3.
I want it to be Persona 5, but I know that it isn't at all possible.