It seems that ATV/UTV manufacturers and RV manufacturers run in cycles, much like everything else these days..... Just a few years ago, Polaris came out with the RZR, advertising it as the only UTV capable of navigating trails designed for ATV's. Most trails, in Michigan anyway, are 48-50" wide and most UTV's were 60+ wide. Then, along came the RZR S, then the RZR4 S and now the even larger RZR's with tires nearly as big as the rear tires on my tractor.... As they "grow", the RV manufacturers come out with toyhaulers to carry them.
Seems that we're in the cycle where the RV's need to catch up to the UTV market. Rest assured, as soon as someone builds a toyhauler big enough, the UTV manufacturers will come out with a model that's too big to fit......