What's your most insane theory that you believe even with zero proof?
Mine is that Argenti is Idrilla. And I mean, he literally is THEM, he just doesn't know it due to some wacky stuff yet to be revealed. Maybe it's reincarnation, maybe it's amnesia, it doesn't matter, he is Idrilla. That is why he is completely obsessed with following his path, and why he does the most absurd things imaginable.
Saving Aventurine is suddenly a lot more plausible when done by a literal Aeon.