It's not just the Emprah. There are many plot holes, inconsistencies and contradictions because of late rewrites(and different conflicting visions for the characters and story?) which show up at the end of act 2.

An example: Balthazar doesn't know where the Nightsong is imprisoned even though he is the one who drains her power for Ketheric? Why? Well, because originally the Nightsong was a pretty different character.
https://bg3.wiki/wiki/Aylin#Datamined_content

Another example would be romanced Shadowheart. From act 1 Shadowheart is supposed to be the "sheltered girl with overly strict parents" which is why during the Tiefling party even though she was happy she said lady Shar doesn't approve of it. Enter evil Shadowheart who tells you that Shar's teachings didn't allow for flings but she still did it in secret anyways. Then cheat with Mizora and Shadowheart tells you flings were encouraged so which one is it??

Sure, the Emprah is most guilty of this especially since he robbed us of a Durge vs Orpheus vs Tadpole three way battle. I don't understand why they added him in the first place to be honest. Just make the tadpole dreams pop up even if you don't use the powers?

Also, add in an unnecessary origin system with only one real origin that makes sense which sadly isn't even fleshed out. Yeah, the more I think about it the more I think a rewrite would be nice.