I’ll admit that I haven’t watched any of the movies you’ve listed here except Gods of Egypt, which I thought was sub-par at best, but I do have some thoughts on this.
Mythology is a bit of a tricky subject - the original material is shaped by individual cultures and thus some things can be strange or foreign to some audiences. Take, for example, original Norse mythology. All the gods of the Aesir (or most of them, at least) struggle against the inevitable Ragnarök. This fight is tied to a key Norse “virtue” (for lack of better term): bravery and resilience in the face of impossible odds. With this in mind, it’s easy to understand why Odin is trying to prevent Ragnarök despite knowing it’s inevitable, but without this key tidbit, it would seem that Odin is crazy.
It’s very easy to understand and even adapt Norse mythology if you keep that in mind. Films could be made in which that special virtue is made out to be some sort of desirable goal. However, audiences may not be well-educated on Norse mythology (the only reason I know this is because I’m taking a theology class!) and thus would view Odin as unrelatable and artificial. He would have to be insane or poorly-written - why else would he be doing these absurd actions?
I think similar things apply to just about every other mythology out there that was “thrown out” (in other words, mythology human civilization did not integrate into the bigger picture). The concepts are too foreign for us, especially in mythology with values contradictory to Christian doctrine.
I know Christianity isn’t exactly popular at this point, but it is impossible to say that culture as we know it was not formed by Christianity. So, Christian values are more or less at the heart of everyone’s worldview and thus we have certain vague notions of what virtue is, or what evil is, or what is brave versus suicidal. This makes certain mythology incompatible with modern audiences. Sure, a producer/writer could try to overcome this by rewriting the mythology, as seen in Gods of Egypt and presumably the Thor movies, but now you’re dealing with Christian or semi-Christian values in a pagan setting, where it doesn’t fit. Not to mention the new fusion would be highly inaccurate to the mythology.
As an extreme example, that, as far as I’m aware doesn’t exist, it would be like turning gladiatorial combat into a Sunday football game - and then having the movie portray this in a positive, normal way. Romans certainly enjoyed the barbaric games, but to our Christian-influenced eyes the practice is grotesque and cruel.
Long story short, I think the reason so many of these mythology-inspired movies fail is because they are trying to make these stories palatable for modern audiences, but the stories they adapt already tell a message that can’t be changed. Then again, I might be crazy, I’m still interested what everyone else’s ideas are.
[EDIT 12/27/2023: I just watched 300: Rise of an Empire and have some follow-up thoughts.]
300: Rise of an Empire (hereon “RoaE”) was a poor adaptation of the history of the Greco-Persian War. I’ll be the first to admit I’m not an expert in this area of history, but they took severe liberties that made the entire thing more of a fanfiction than an actual movie about heroes of the past. Granted, they were not trying to make an accurate movie, but it seemed while watching it they were conflicted between a historical sci-fi movie and a normal historical fiction movie.
The entire thing seemed to hinge on the recognition of the original movie, 300, as well. 300 was a decent movie with some good memes and an actually acceptable story. Sure, as a history nerd, I did not appreciate them making Xerxes some sort of freak and adding in all kinds of grotesque images to make Xerxes even more of an antagonist, but I can recognize it was all done for a purpose - to make the Spartans look more “natural,” more “relatable.” Overall, the movie wasn’t my style, but it was acceptable I suppose. This does relate to my thoughts on RoaE, by the way.
RoaE was trying to make Themistocles into a sort of Athenian parallel to the Spartan Leonidas. Spoiler alert - it does not work. The reason 300 was good was because the value they were trying to convey is something we in the modern age can understand - die standing rather than live kneeling. Everyone knows the Spartans as well - they were the war-hungry and ridiculously good warriors. The Athenians, on the other hand, were the scholarly artsy types, and yet somehow, their character development is made to be the same as the Spartans. My genuine first reaction was “They made a knockoff of their own movie!”
I think this may be a problem with a lot of mythology adaptations: the formulas in said mythology are the basis of essentially every other story, making their plots predictable. When producers try to rewrite them, they all of a sudden have loose ends and miscellaneous characters, or have to add in historical inaccuracies to cover up their poor writing.