It isn't that one doesn't like to "do" things or not have interests. It is that the world changes, you change, life changes, and interests evolve and many folks develop new ones. And it seems that you discount the effect these things have on life. It is really easy to say that, "my interests won't change much" when you are on the end of youth. More to the point, though: Your brain hasn't quite stopped developing. You've not reached the change a lot of folks experience in their late 20's. And so on.
I mean, I moved countries (permanently) at age 35. (I'm 40 now). I've learned a language (not fluent yet, but still). I've had times where I've simply not had the time and/or the inclination to do much with my main hobby (art), and over the years it has changed vastly. Other things have came and went, no matter how much I enjoyed them at the time. I didn't guess this stuff would happen to me at your age, though. Life happens. There is no point in trying to speculate on these things, especially if they risk keeping you in a set mindset without evaluation over the years.