Rode bmx all over town as a kid to get to friends houses the golf course, etc. We would build trscks in the woods with tabletop jumps and whatnot.
Picked it back up as an adult when my oldest daughter was a few years old and starting to ride.
Geeked out on the history of brands and globalization of manufacturing. Thst led to geeking on theory of materials and geometry.
Got into longer and longer rides for the same reason so many adults get into endurance sports- its a challenge we can still accomplish even without the fast twitch muscles and strength we once had. Furthermore, with little to no suffering in life, endurance sports mimick that struggle, which is appealing for many.