School success does not imply being smart, wise or knowledgeable.
Failing your school classes or hating school does not imply lacking brainpower or lacking learning capacity.
Hating school doesn't mean you hate learning.
Enjoying school of getting A's does not mean you like learning or understand the topics covered in your classes.
These things aren't significant hints or clues. There isn't a strong correlation. You can't judge people by their relationship to school.
On the high end, if you're really great, that clashes with the conformity and obedience that school asks for. But being great can make up for it. If learning the material is easy for you, that advantage can lead to school success even if, e.g., you don't respect your teachers. It doesn't have to lead to good grades but it can; the result can go either way.
On the low end, if you're bad at thinking, that can lead to pretty good grades if you just do as you're told, make a visible effort, and have low starting points to improve from (teachers often give good grades for improvement instead of just for actual results).
If you fail a bunch of classes, it could be because you disliked them (with cause) and skipped classes or didn't pay attention. This can happen if you're smart or dumb or in the middle. There's stuff to dislike about class for everyone.
If you get bad grades, it could be because you saw how pointless it was to memorize things for a test and still not understand them. Maybe you didn't learn the material but at least you knew you didn't understand. Most people who pass don't understand the topics either, they're just e.g. more willing to pretend their confusions are successful learning.
If you get pretty good grades, you could be a stupid, obedient conformist. Or you could have seen lots of flaws in the system but been under extreme pressure from your parents to find a way to get pretty good grades anyway. Or many other things.
Don't judge people by how they did in school.
And especially don't judge yourself by how you did in school.