Not gonna reply to any one specific person here. Just to say there's a lot of mixing up of aesthetic preference and practical implications going on.
Aesthetically, I think P1+2 have the best Predator designs. While there are aspects of the later films that I like, the overall execution of their faces particularly has always felt off to me. And you can see a clear change as the years have gone by. But you can't really make arguments about the jaw structure of a fictional creature from any kind of scientific standpoint as has been demonstrated already by SiL's point on dog breeds. Truth is often stranger than fiction.
The video linked in the OP actually showed up on my YouTube feed a few days ago and I watched it then. I found myself agreeing with the sentiment behind the video, but like a lot of YouTube critics/video essay guys I think he falls into the trap of conflating his subjective opinion with some sort of objective truth he can actually argue about successfully. And he can't, relying on his own assumptions and false information at various points to underpin his argument.
I think it would be a lot more beneficial if people gave up on talking about 'why xyz is objectively the best/worst thing to ever happen to the fandom' and instead exploring their own interpretations of those things. Why do you feel a certain way about Predator face designs? What are your thoughts? Share your opinions as what they are: Opinion. Don't try to dress it up in some pseudo-factual disguise and force your views on others. It will never produce the desired result and you will just end up irritating one-another.
So ultimately, while I feel like the creator of the video is probably on my wavelength from an aesthetic sensibility standpoint, I can't agree at all with the way he decided to go about expressing that idea.
If I were to boil my views down to a relatively snappy summary of Predator designs it would be this:
The original Predator designs in the first two movies had a slim, athletic look that helped make them convincing in their role as fast and powerful killers from an aggressive, ritualistic culture. The texture and the design of their bodies helped sell them to me as genuine extraterrestrials with functional anatomy.
In more recent portrayals, the designs have changed somewhat. They're still immediately identifiable as the same species, but proportions and facial details have drifted away from the original concept. The proportional changes have detracted from the sleek, athletic silhouette the creature is associated with in my mind. Meanwhile the changes to the structure of their faces gives me less a sense of strange alien anatomy, and more a sense of looking at a costume, designed by human hands. The way the designs have been done more recently just doesn't feel as convincing or 'alive' to me.
