The video addresses why they did it on purpose: it suited the script. Then they had to reuse the moulds for the next two movies. And they've been consistent in saying that from the beginning.
They have said they didn't like the literal nuts and bolts on Giger's original suit, but then immediately talk about trying to stick closer to the look of his paintings - which they really did for A3.
I've never seen anyone here say ADI is beyond reproach, or act like it. The number of people who hate their Predators, or their Aliens, or the Newborn, or the PredAlien, basically covers everyone here.
And before you say I'm acting like they're beyond reproach, I hate the AR+ design regardless of whether it suits the story and their chestbursters are the goofiest looking things ever. And the PredAlien is awful. As were Scar and Wolf's faces.