Here's MY thing
After watching this last night for the first time, then coming here right now and reading peoples (valid) complaints about the lack of engineer content, the predictability of the David vs. Walter switcheroo, the boring deaths, etc. etc. and nobody seems to have touched on my biggest disappointment, which is:
After all of the films since the first 1979 beginning, everyone wondering about the xenomorphs, the space jockeys / the engineers, all other aliens to date (including the precursors in Prometheus), it turns out that a whacko robot is responsible for killing off the entire engineer race AND the creation of the xenomorphs as we now know them (the ones Ripley kept having to tangle with)?!
That is, David, a human creation -- Weyland's creation -- turns out to just be the same crazy-android-feeling-superior-over-creator, not-having-kill-human-failsafe tropes that we've read about in books and have seen in sci-fi for decades now?
Scott is not alone covering this old ground as we had just sort of had in Ex Machina. But he's been at this so long that I was expecting better, hoping for a more unique pay off.
The solid sci-fi mystery around this killer species that we were first introduced to, with Weyland (Lance Henriksen?) and the company man (Paul Reiser) wanting to bring to earth for nefarious purposes, is something Scott is now resolving as being our own doing? Because of a mentally ill early-generation robot?
A mystery that, no matter how you feel about Prometheus, was still maintained by the whole first engineer, the seeding of earth, the new discoveries by Shaw and crew, etc.
Poof. "You shouldn't have brought that sick android."
I guess it's always been about an iffy android, right down to Ian Holm's Ash wanting to shove a porno mag down Ripley's throat, something we got a bit of in this film when Daniels uncovered David's "H. R. Giger" inspired drawings of a female-looking being with the mouth orifice full of something tentacle-like.
What's the point then of what is now called "Untitled Alien: Covenant Sequel"? To resolve things sort of like George Lucas's 'Revenge of the Sith', to quickly wrap up how we got from here to there (or more properly, there to here)?
Lame!
The only thing left for Scott to do is provide David with a space jockey to have a chest to burst. He now has a couple of thousand colonists to goof around with (AND embryos) -- I'm sure he'll think of something.