And considering how creepily manipulative Daisy was in EA depending on how the player treated her, the Emperor's personality behind the persona at the time was likely written to be 10 times worse because Larian clearly wanted him to truly embody what a mindflayer is. A heartlessly cold, calculating, manipulative psychic control-freak with far less moral ways to achieve his goal because he was quite literally willing to sacrifice the entirety of the Sword Coast using us as his Chosen, including us if we proved too stubborn. We were quite literally "his beautiful weapons", as Shadowheart still mentions even in full release.
Having a similar personality does not explain why Daisy had to wait for the player to start using the tadpole powers to be even able to contact them. You needed to use them a few times, once was not enough. The emperor is in control of the prism (or rather Orpheus). So why would he shield himself (in EA) from being able to contact the player?
And if you recall the old Shadowheart encounter that happened if you did not recruit her, the way the prism extended influence over her was not through the dream lover. It befudled her mind, the voices telling her to find you. That encounter was even in early EA, because I've managed to trigger it on my first playthrough.
On the other hand, if Daisy were your tadpole, it would make sense, because the tadpole was not likely to be in control of the prism. Perhaps the emperor was sitting in the prism already (but was lacking the means to communicate), perhaps it was only Orpheus, but it seemed to be protecting you from Daisy as well as the absolute.
