If you’ve got too much time on your hands, you could try to see everything at the Miniatur Wunderland in Hamburg, Germany. That’s just looking at it. Building it involves too much time on many, many hands.
Model trains used to be a fairly common hobby. I’ve been in lots of basements with sheets of plywood on sawhorses with trains not currently running around them. They were artifacts of earlier times. Great-grandpa’s trainarama. Grandpa’s train obsession. Mom’s abandoned trainyard after she threw dad out for spending the sugar bowl money on HO scale houses instead of a new roof on the actual house.
Human beings dabble, that’s for sure. Otherwise there wouldn’t be an exercise bike being used as a clothes horse in every bedroom in America. But some people, weird and wonderful, take things all the way to the end of the line. So to speak.