I think anyone can be too dumb for anything. Personally, there are many things that I feel like I am too dumb for. Specifically things that require artistic ability or emotional thinking. Even as a kid I find subjective topics completely baffling. I always loved math because I was either right or wrong, and I liked science because my hypothesis was some variation of right or wrong. Could I learn an instrument, sure, but by the time I get any good I could have gotten substantially better at something that clicks for me.

Don't get me wrong, if you find it interesting and have passion for it, that could probably overcome what you are lacking with enough time.