Sure. But AI doesn't make you bad at hobbies. It just makes others better at it, and even that is a stretch.

>I've been learning the piano recently and striving to play more difficult songs is what makes it fun.

And are you going to give up learning piano because now AI can just generate piano music better than anything you can ever produce? No? Then what you're doing is a proper hobby, which contrasts with the OP who feels their efforts are no worthless because AI can just do it better. That's not really a hobby; it's a job.