Emperor still has his own mind intact
This statement is debatable ...
Mind Flayers are DnD version of "ship of Theseus" ...
(Feel free to google it, if you dont know, its quite interesting thought experiment.)
Regular tadpole is creating complete copy of the Host ... it feels reasonable to expect newborn illithid to see themselves as previous person, even if that one is no longer there ...
And over time, as they consume more and more brains, they are not just consuming matter, but memories and experiences aswell (that is why The Emperos is able to steal that shielding ability from Orpheus ... by eating his brain, he litterally learned how to do that) ...
Meaning the Mind Flayer starts as the Host ... but as they keep on living, they are slowly becoming amalgamation of all people they consumed.
(Fun fact: That is why its bad idea to let Mind Flayer only eat criminals, you are growing yourself one first class psychopath ... oh wait. xD )
