> Also (3) I don't get, because while I am extremely motivated by intellectual curiosity, I have maybe zero motivation to "develop my intelligence" like it was some kind of fitness thing.
Given the amount of cognitive bias each of us has, I'd say an important part of intellectual curiosity is making effort to learn to think better. I mean, a flat-Earther 9/11-truther astrologer could still claim to be primarily motivated by "intellectual curiosity".