There's this moment where the Stargazer people show Olivia Munn the Predators from '87 and '97 on a tablet and it's literally screen captures from the first 2 movies... one of which being the Predator when Dutch was covered in mud, when it comes out of the water and it can't see him. Like... someone was there and took that photo.
This movie had no pacing and it was edited so badly that you can tell there was no thought-out complete story while they were filming it. If you've seen it, you'll know what I'm talking about. In the teaser trailer, McKenna says, "We're assassins. Isn't posing a threat kind of the point?" In the redband trailer, McKenna says, "We're rangers [as it shows the guys from the bus]. Isn't posing a threat kind of the ****ing point?" In the movie, McKenna says, "I'm a sniper. Isn't posing a threat kind of the ****ing point?" Why were there 3 alternate takes of the same scene that completely change what he's saying? In the redband trailer, when Olivia Munn is handcuffed to the chair, Sterling K. Brown is introducing himself and talks about how Predators conquered space. In the movie, it was well past the point they'd already met at the Stargazer lab. Multiple instances like that where things are in the trailers that aren't in the movie at all, such as McKenna looking up at the sky and saying, "come and get us mother ****ers." In the scene where the looney crew is getting on the RV to escape the middle school while the big Predator kills the fugitive Predator, it shows a pitbull from the football field running toward them and it cuts away. They don't take the dog with them and the dog is never seen again. You can't tell me Shane Black is a smart writer and had a vision of what he wanted when he made this when the whole thing was cut and paste scenes from alternate stories.
Jake Busey's cameo as Keyes' son leads to nothing or any exposition dialogue about Peter Keyes from P2. At no point does anyone in the movie talk about hiding their body heat from the Predators. For some reason Olivia Munn is able to sneak up on the big Predator at the end by using the invisibility orb... which shouldn't mean a damn to a creature with heat vision. For some reason the Stargazer base has the mask from P1 but not the mask from P2 that was left behind at the slaughterhouse. Just a lot of WTF things that could have been easily fixed with a script doctor.