This is a pretty interesting observation (to me). It's interesting because I think it reflects different "apprenticeships" in MTB. Around here there is essentially no singletrack riding that would be considered "non-technical" in many areas of the country. So if you go on a half-dozen rides you've either achieved a certain amount of mastery of rocks, roots, stumps, and mud or you've given up and gone back to tennis. Certainly this was true 20 years ago when I first started riding MTB. (There are starting to be some machine-built trails around here that are not all rocks and roots.) Conversely, you could and still can ride more or less indefinitely and never have to get comfortable with jumps. There WERE jumps, but they were, you know, integrated into all the rocks and roots, so you had to be able to cope with BOTH. There were no "man-made" jumps with nice smooth open landings. Anyway, because of all this it's only recently that I've started enjoying the air time. "Riding off the end" still gives me pause, yet I can ride through rock gardens more or less in my sleep.