Except for those fulltiming or longtiming I am guessing that North America will follow the Europeans & discover that smaller is actually better. It took Detroit an awful long tme to build smaller cars, down from the land ships of the 50s-80s, encouraged by higher fuel prices though gas in the US is about the cheapest anywhere.
The Sprinter styled RVs are gaining in popularity now along with lighter towables. There will alaways be a market for the few who simply must bring the whole house plus toys for a 2 night weekend.