Some background is in order.
In grade school, I enjoyed math. But when I got to junior high, the school didn’t have enough math teachers. So for grades seven and eight, we were warehoused and checked out ‘workbooks’ every day. If we didn’t disrupt, we got an “S” for satisfactory on our report cards. But no math instruction for two years. In ninth grade we were put in an algebra class taught by a good but demanding teacher. Most of us did poorly, and assumed that we weren’t capable of learning math. It wasn’t until I’d gotten interested (in my early 20’s) in electronics and wanted to study engineering that I gave math another crack. It was hard for a while, but I eventually succeeded.
I often reflect that I came very close to becoming an adult who assumed that I was ‘not a math person’. Would I as a result have ended up a bum, or a criminal? Probably not. But I shudder to think of career opportunities and accomplishments (not to mention enjoyment) that I would have missed out on.
Because of my experiences, I clearly carry a bias when I hear people describe themselves as incapable of doing math. I believe that many such people have been soured on the study and understanding of math by bad teachers (or, as in my case, badly run curricula). Such discouragements are cumulative - one bad one can turn a person off for life.
As I relate in post #63 upthread, I blame a lot of this on the ‘sink or swim’ attitude that schools took towards instruction when I was a kid (I’m 56).
Is everyone capable of doing math at the college level? Of course not. But not everyone is capable of college level work in any subject.
How can you tell whether you are actually capable of learning math? Well, one indication is if you’re smart at other academic subjects. Especially ones that involve logic and rules, like languages. I’ve met people who are whizzes at foreign languages who think that math requires some rare, savant-like ability. I tell them that I’d be just as clueless communicating in a language I hadn’t learned.
Many people who never learn math do quite well in life. Your son might well be one of them. Much professional work involves researching solutions of problems performed by others.
But if that’s all you do, you are relying a lot more on those others than if you’re able to check their work.
For most people who know math, it’s nothing more, or less, than a very useful skill.