I'm 27, and I've found that I actually am more interested in coding at home now than I was at 22. I can't stay up as late as I used to, but I find that I am able to be more productive, and hence happier, because I wound up eliminating several things that were huge distractions back in the day.
For instance, I stopped drinking about 4 years ago and cancelled my cable because I felt that alcohol and ready access to television simply weren't adding anything positive to my life. If I want to watch a football game, for example, I go to a sports bar and call a friend - killing two birds with one stone. I got married and that gives me a reliable outlet for sex and socialization that simply wasn't around earlier. When she wants to do something together, it does interrupt my coding, but on balance it's less of an interruption than dating ever was.
I think it's not as much about how much time you can pack into your day as how well you've learned to spend the time you've got. In my experience, age has only helped me there.