Yeah, there probably is some nihilism in there.

Though I remember in my late teens I turned into a bit of an adrenaline junkie for a while. I went skydiving, would ride on the exterior of vehicles speeding around, etc. The reason I did those kinds of things was because it was only when there was a risk of dying that I would feel anything at all - yet even then I remained mostly numb. My reaction to skydiving was "Yeah, that was all right" whereas the other people who had jumped were hooting and jumping around after.

That is certainly something to think about as well. I would wager it's because people in the Western world are always living for the future, and so put off living in the present. But then that future either keeps getting delayed, or never comes. They grow old or die before getting a chance to live, and so are not at all ready when it comes.