I don't think it's a matter of being bored, he's probably like me & doesn't like to feel confined, he gave up a 35 footer to go to a 21 footer, probably to make you happy, obviously he isn't happy with the change.
To me that would be akin to moving from a house, to a closet, I have a 29' class C, I would NEVER go smaller, & I'm happy that my wife wouldn't let me.
Unlike others, I don't have a problem with a C, when I get set up, I'm there for the duration, we do take a toad with us, but that makes it easier to tour, site see, or go shopping, & it gets 34 mpg while doing so.