Bruh, what cherry picking. Literally in the exact same movie you have velociraptors stalking prey in groups and the dilophosaurus doing their own patronizing thing. If we look to other movies, you’ve got Xenomorphs, you’ve got tremor worms, you’ve got pumpkin head, you’ve got Moder (The Ritual), you’ve got the Blair Witch, etc.

There’re plenty of good stalking monsters in film, some of which that you don’t even know are there till it’s too late.

EDIT:also, we see literally a few scenes later the T-Rex come outta nowhere and grab a gallimimus no problem, so they’re even shown to be decent ambush predators in the same movie.