It's baloney. It's kind of like the old adage about how kids in dual-language families develop second-language skills at increidbly rapid rates but adults have to take years of classes. I'm sure there's a degree of truth to it, but I always thought the reason was because the kids were immersed in it and really didn't have a whole lot else going on. My friends that moved as adults to Mexico to learn the language were fluent in 6 months due to immersion.

As an adult you have family, mortgages, taxes, work, etc. on your mind all the time and might not be able to spend the required time on learning the keyboard.

You're 15. You can do whatever you want. The only difference between you and a kid that started at 8 would be the 7 extra years of lessons the kid had. Never too late and you'll develop perfectly normally in my opinion.

Now take a keyboardist like myself, and try to learn guitar at age 32, and that's a whole different ballgame! I failed miserably.

Good luck!

Tommy