For myself, I can’t read music and play at the same time. Yet, if I hear a piece, I can play it on the piano or whatever instrument you throw in front of me. Yet, I don’t ‘get’ music theory. So, in my case, music is a weird innate ability.
Math-wise, I always did well in school (except geography + calculus, but the algebra stuff was fine), yet here’s how my brain works:
I always break things down to their simplest components, then I complexify them just to reorganize and then simplify them again. I can’t go simply from “A” to “B”. I have to go from A to Z, Z to A and THEN I’ll go to “B”. I’m wired differently than most people. I think in terms of practical possibilities, then fantastical notions, gather whatever usefulness comes from the fantastical notions, just to return back to NEW practical possibilities. I reuse known information to create new information.
the same takes place in music. I hear something or it comes out of my head, and I don’t directly imitate it, but I use it as a jumping of point to create something that’s partly inspired by what I’ve heard or thought or saw, along with a style that fits my playing.
So, in my case, it’s not so much Math related, but rather brain-processes related. It’s a coordination of fingers and arms and brain and being “in the flow”, more akin to the coordinated yet creative efforts of basketball players or other sports where the skills are there to respond to the external stimuli. Every game is different – your role is different, yet its still a game where your role is similar to games in the past. Playing piano is as much a sport as it is an art form.
But it depends when you say “music”. I can well imagine mathematical people would have precision in mind. Exacting repetition. In my case, I’m less a mathematician and more a scientist, adjusting parameters, running experiments, adjusting again. It’s a process towards a goal (conveying a mood).
I have a skill in music. I have a skill in computers. I can write programs. I can use LOGIC without being bound by that logic. You have to be able to create paradoxes if you are to make music. If I feel a need to reach a goal, whether it is a program or expanding upon a “ditty” in my head, or solve someone else’s problems with money or decision-making,
So is math helpful to playing the piano? it can be, but it depends on the type of piano player you will be.