Yeah, looking back, it's a pretty harmless line; I just hate the "____ killed the dinosaurs" trope.
Having said that, AVPR just
had to have that damn Triceratops skull, so clearly they've hunted dinos. Maybe some other ET species snatched a few from Earth to put in a zoo or something (putting dinos in zoos always ends well), and the Preds came upon the wild descendants of those animals millions of years later.
In any case, Ice Age megafauna makes more sense - narratively and in terms of novelty. We need a good cover for the next Predator anthology or comic anyway, and I'd rather see a painted, Frank Frazetta-style clash between a Pred and one of these bastards:
https://i.pinimg.com/736x/2e/77/05/2e770514d15f39d7d551cd55dc63ff87.jpgthan more badly photoshopped promotional pics.