I am 60, with 28 & 30 yr old children and 3 grandchildren. I haven't seen them or any of their friends decorating their homes like these RVs. If anything, the younger people I know (who actually decorate) tend towards lighter palettes. And a lot of them just don't care.
You are right, though, most of the negative comments I heard were from people about my age. BUT we were also over half the attendees at the show, by my estimate. We are also the ones buying the higher dollar RVs, and we vote with our checkbooks!