This is a work of fiction.
You're going to tell me : science fiction. But SF is a very large thing, that encompasses many genres. Hard SF is only a sub-genre of it. SF has become a loose word, it seems, which is maybe the core of the problem (and I think that there are maybe problems in some areas in what regards distinctions between fantasy and SF).
There are people that like or only like truly hard SF. There is nothing wrong in that... Except when they criticize works that are not hard SF by using hard SF arguments.
Another problem is the fact that in SF the fiction
element prevails 90% of the time (I'm gentle). It is a literary/cinematographic etc. genre. The science serves the story, not the inverse.
But only a complete fool would attempt to portray the ancient history of human beings as the pre-determined work of a fairy-like 9-foot-tall race of slap-head giants.
I don't see why. As an idea, it is 100% valid to build a story upon. What matters here is the execution. As for the science aspect, there are several things to consider : it can be the scientific truth/reality of the universe of fiction where the work is located (what matters is the coherence of the fictional universe). 2 : there is no problem with the notion that a very advanced species can create/manipulate life, leading to a human-like species. Unless we deal with a more drastic approach, but that would be coherent (for instance, the SJs or aliens control and manage Earth's ecosystem for millenias, or I don't know...). 3 : we haven't seen the movie
: if the SJs or another race has been instrumental in the homo sapiens origins, then it's by modifying (mutation, strange black veins, huh ?) other hominids, or it can be simply by helping them for example (Prometheus with the fire).
In a work of SF, I've nothing against a well-made and well-grounded "ancient astronaut" basis. I can even accept a bit of facility in the concept, if the rest is good.
I would be more stricken by things like : a Space Jockey that would have the power to create xenomorphs, but that would have a flawed body (naturally very fat, non-symetrical, one-legged, or else
... "Hey, we've just created the "perfect organism" to destroy ennemies ! - Cool, maybe you should consider upgrading yourselves a little bit." (that's for some artistic interpretations of the SJs, that are very good... but not in practice
as silly as the ancient astronaut hypothesis is, it is not "true" creationism
The idea upon which Prometheus
is built is good, in so far as it is a "weak" ancient astronaut theory : there has been a contact, but there hasn't been, for example, pyramids built on Antarctica to house AVP conflicts.