Yeah, there's a lot to be said for what the quality of the practice is. Someone just practicing something for 200 hours could see less (relative) improvement than someone who, for instance, records themselves doing something and watches it back so they can find the things they really need to focus on, and then practices those things for 50 hours. Coaching themselves, essentially.

Of course, it may just be that more focused, high-quality practice just lets people reach their ceiling faster and doesn't actually give them any long-term advantage - I don't know. It's something that would be interesting but difficult to study.