I’m an adult student who just started learning violin last month, so I’m discovering first hand that you’re never too old to learn an instrument. Conversely, I started learning piano at a young age (around 7-8 years old), and I found some concepts just too hard to grasp at that age. In other words, I don’t think I was a better student because I was young. I also think there is something to be said for being old enough to know that you want to play the instrument, rather than feeling like you have to. Just something to keep in mind.