while BG 3 has decided to have zero consequences if you go all-you-can-eat on tadpoles.
This is one of the things that bother me, as well. People at my camp made such a fuss about how crazy it is to even consider consuming more tadpoles (and my character did agree), so I avoided them, because I was certain that something bad would happen as the game progressed, like that I'd become (partly) mindflayer, that I'd lose my soul or something like that.
The fact that NOTHING happens whatsoever is really baffeling. Why shouldn't you, on a second playthrough, consume all of the tadpoles?