Or how about growing up gifted and never having to study or put much effort into things up until you hit your peak where you suddenly HAVE to study because there's simply too much information to remember passively, but you have no idea how the fuck to DO that, so you're just falling down into a spiral of depression and impostor syndrome and feeling like your whole goddamn childhood was a lie! I… should probably stop because I kinda teared up while typing that.

People often mistake intelligence with knowledge, is the thing.

A person can have a lot of knowledge and not much intelligence and viceversa. Also, lacking knowledge makes you "ignorant", and only in particular subjects, whereas lacking intelligence makes you "stupid" and has more of a general connotation. That is why school grades are never considered a measure of intelligence, as they measure your knowledge on a particular subject, for which you can study dilligently and pay attention in class and still succed regardless of your intelligence, which is why you can sometimes see things like people with bad grades get a good job and people with good grades struggling to do anything, since professional jobs do in fact require intelligence as well, since you put your acquired knowledge to practical real-life use.