I feel like cheotic evil is a comfortable excuse for bad writing. "The storyline is weak and doesn't make sense? That's because it's cheotic evil!"
I think it makes a lot of sense. Some people are just slower at seeing at the moment; the current story doesn't reveal that much either.
I have no idea how no one even points out an 'ethereal plane spider' down in the 'Whispering depths'. Normally, creatures on the Ethereal Plane cannot attack creatures on the Material Plane, and vice versa. We are all under some sort of illusion, or worse...
Great theory there too bad half of it looks like Chinese to me. I've said it before, if it's not in the game, it's invalid. And I'm not talking about all these Easter eggs themselves, I'm talking about the context that the player need to realize their significance. When adapting anything into something else (in our case, a world setting into a video game) the adapted product must stand on its own. I don't particularly care about forgotten realms lore and I don't know much about it. But if a game set in the forgotten realms is good enough, it will tell me enough about it to enjoy it. There are aspects of FR lore that bg3 explains well enough, for example mind flyers and tedpoles. I don't need to know everything there is to know about them, just enough for the game to make sense. If I need to read dozens of FR lore pages just to understand the story, the story is bad.
Other than that, your theory doesn't address any of the main issues we raised regarding the flaws of the evil path, specifically the lack of incentives to presue it.