Funny, I am in the heart of TC country. There are at least 6 truck campers in my dog walking loop in my neighborhood. In my group of friends that ride quads/dirtbikes/RZRs there are more TC's than anything else. I see a lot of truck campers all the time. But usually they're on a way one drive from home to their favorite riding area or fishing hole. You wouldn't find them plugged in at a RV resort. Nor bouncing from one RV Resort to another RV Resort. And we're all 30-40 years old. So how old is younger? LOL.
And really an interesting study would be the average age of the 1st time RV buying???
We bought our tent trailer when I was 32. 1st RV
Bought our truck camper when I was 35. 1st TC
Just bought a toy hauler now at 41 and keeping the TC.
Buying an RV has so many factors. You got to have some $$ to make it happen so kids and buying your 1st home come into play. Then the size of the RV is dictated a lot by how much and fast your family grows.