Making sure that AI factions play in their respective little boxes and not beyond them does not equate to maintaining historical accuracy in a strategy game ( games should have some fluidity in them). It's more akin to "History of X: every year" videos one finds on Youtube.
I never said that AI Egypt should go west at the expense of the east. I said that AI Egypt should have the freedom to go west, and that that freedom is maintained via an African land route - due to the limitations of the game engine.
You're heavily influenced by your own hegemon-like play style and you're trying to insert the tug of war with no clear winners status quo you like as much as possible into the game. That only results in a less challenging and far less rewarding game for the player. Fighting smaller factions, factions that are exhausted by constantly squabbling with each other is far less interesting than fighting a strong faction.