Yeah, my mom also decided that I would play piano at a young age. It turned out that I never liked it, never enjoyed it, and never really had any desire to progress in it, but it sort of became a "we bought you a big expensive piano so shut up and practice and be grateful" kind of thing. It didn't really end well, and I was never any good at it. I realize that a little kid is probably going to change their mind quite frequently about what they want to do, but there's something to be said for not forcing the kid to do something because it's your dream.
And in high school, when I first learned to drive and started working, I started taking learn-to-skate lessons. Never got any encouragement from my mother (also frequently got the waste-of-time line), but I really did enjoy it. And sure, I was never spectacularly good at that either, but I did it because I genuinely wanted to do it, so it was a LOT of fun