Ok so this is all wrong. I get that the tadpoles we have inserted into our minds are special, different from all tadpoles that have existed in D&D before in that they are put in stasis through the use of shadowmagic but it goes way further than that. I will put this in spoiler tags but know that I will only describe the issues I have in generic terms without going into specifics of the BG3 story like which characters are affected, in which events, or during which acts, etc.
So the game seems to treat the result of ceremorphosis VERY differently than D&D in one key aspect...too many of the mind-flayers in the story seem to maintain the full personality of the host completely...as if nothing changed for them other than their body. In terms of D&D this is unheard of outside of Illithid fears of ever being one such mind-flayer which they label as "The Adversary" but it is not something that has ever actually happened in D&D before. In BG3 there are a lot of such mind-flayers, or characters who can potentially turn and display this behavior. The game does walk it back a little bit later on suggesting that this retention of full host personality is only temporary and that once turned you are indeed on a clock and you will become just another illithid sooner rather than later but even there it leaves some doubt...suggesting that how long this would last is also down to the strength of character of the host. But here's the problem: that's NOT how this has ever worked in D&D. Once ceremorphosis is complete mind flayers in D&D are just that, mind flayers, the host is gone...there's no more time, the host is dead and gone by the time ceremorphosis is complete.
So what exactly is going on here? Is this in agreement with Wizards of the Coast? I imagine it has to be, but is this something that will bleed into the wider D&D beyond BG3? The next gen player handbook for D&D is coming next year, is this a planned cataclysm that will be adopted into the next gen as a means of introducing a drastic and major shift to how Illithids work in general? For the previous gens of D&D they had some cataclysms involving Mystra and her various deaths as a means of justifying fundamental changes to how magic works. Is this the future of Illithids in D&D? To say that at least some colonies and tadpoles were changed by shadowmagic and now work fundamentally differently?