It says set 300 years ago now? But they also said earlier it was set before Europeans arrived in the new world, which was not 300 years ago. They also say it's the first time Predator came to earth so basically all of those stories from the past involving Predator (not that there were many stories set in the past) are now not canon, besides that and more importantly, now they have severely limited their story capacity, now they can only go as far back as 300 years ago in future movies, unless they retcon this one.