We talk about this on the car side all the time. Driving and riding are a lot of work. Riding, in particular, is quite physical. I don't do engine overhauls with my kids, but I do do diagnostics that use a laptop and OBDII software. It puts it in their mileu. Maybe one day they will get up with the hardcore dirty stuff. I hope!
Part of the issue today is the culture of instant gratification, and part of it is that we are distracted by everything.
I'm old enough to remember how emissions controls were going to destroy the automotive aftermarket industry, and young enough to remember when the internet was going to destroy the shopping mall.
C'ars and bikes aren't going away. But they probably will change.