Oh, yes, the guardian doesn't want you to use the purifier that's clear. I'm talking about the narrative at the end when you conclude that you have been permanently altered.
I mean the first meeting with the Guardian that happens on day 3 or so. They show up saying "I came just in time. You were transforming . . . "
I think the guardian tadpoled us, let us cook for three days and then stopped the transformation so we just altered enough to be receptive to it's manipulations. At that point our brain is at least 1/8 illithid.
I’d rather not go too far down a rabbit hole about this, because I’m really interested in people’s head canons, but the scene your referring to gets triggered when you first enter the goblin camp and you’re hit with that huge wave of telepathic energy telling you to transform. So it wasn’t the Guardian waiting, there’s an explanation in the game for the timing. I think the long rest system can be a little awkward sometimes when it comes to cutscenes like this. The Guardian is also still fighting the Honor Guard at this point, so their focus is in multiple places. I know The Emperor is manipulative, but I think he gets too much credit for doing things that have other, far more plausible explanations.
Oh, I forgot to add: Yes, they tadpoled us. They deserve full credit for that, lol.