Personally, I’d be wary of anyone who claims to have a definitive answer. There are so many variables that make up any single application decision, there’s no way anyone can know the formula and say the music supplement (or sports or government or whatever) adds a factor of “X”.
What I will say is that, over the years, I’ve watched various friends’ kids and son’s school mates apply to and get into and rejected from the tippy-top exclusive schools and those that get in all have significant achievements outside of school/grades/test scores, and not necessarily just a long mind-boggling list of activities, but things that show personal initiative and real engagement.
So, a college application is essentially your resume and you want it to represent all of you. If music is an important aspect of you, I would find a way to include it. FWIW, one of my son’s advanced jazz classmates just got into Stanford (ED); he’s obviously a good student, but is also a good musician.