That too, in some careers you have a chunk of memorizing like med school, but in school it's just shouldn't be an important part.
Memorizing is an effort too, but usually smart kids memorize easier when there is interesting topic linked to it, like dates in history, authors etc...
Honestly as a kid I wouldn't have bothered to learn from just memorizing an exam.
And yes, even though it wasn't like that for me, internet has taught me a great deal still, what a time to be alive! (That's the catch phrase of two minutes paper, great YouTuber to learn about computer sim / AI)
Listening to the teacher is the willingness i'm speaking about, and taking it in require effort. That effort can technically be lessen by intelligence.
However having a bad education system will drive intelligent people to drop it and be unwilling to learn in the first place. I guess that's really what you meant.
I didn't go to school in the US so I can't say if they are that terrible. Where I live they were always some teachers to raise the bar.
That said if the richest didn't finish school, those who haven't finished school aren't all rich. Plenty of them dropped for the wrong reasons.
Furthermore getting rich isn't always the goal, some smart people are passionate about subject that doesn't pay as well but does require extensive study. For instance sciences are such fields.
Unfortunately deciding if school is or isn't for you isn't much a matter of intelligence rather than wisdom.