Among the “RVer” crowd I think this evolution happens quite a bit. But it’s certainly not predestined for everyone. I know many people who, like myself, like to leave civilization a few miles back. They don’t go through this evolution simply because they would shortly be prevented from getting back in where they want to camp.
My evolution has been more types of RV’s than size. I tent camped for almost two decades and was perfectly happy. But as I traveled more, tent camping became a PITA because of the constant packing and unpacking of the vehicle. So I bought a PU and that worked great for another decade. Then when it was getting well worn we went to a 16’ TT. The DW wanted a bathroom and more storage and organization. And I think she felt a little more secure in a hard side though she never admitted it.
I pulled the PU with a car and my ’73 Bronco, but they wouldn’t pull the TT. But by then I had an ’86 Bronco which pulled the TT fine. About six years later I replaced the Bronco with an F150, which pulled the TT better. But that wasn’t an upgrade to pull the TT, the Bronco had over 100,000 miles on it and I tired of the frequent ac and fuel system problems. So another decade plus later I still have the same TT and TV. I have looked at going slightly bigger, up to 19’. But we’ve never found a floor plan we like; permanent beds or large bathrooms make the units feel too cramped. Even then, though, I wouldn’t have to upgrade my TV to pull it.