I bought a 4X4 for one simple reason: So many truck buyers have been convinced by the marketing folks that they MUST have a 4X4 that used 4X2 trucks are nearly impossible to find.
Besides, I liked the aftermarket front bumper/grill guard!
I towed a fifth wheel for over two years, full timing, with a 4X2 one ton dually. Never got stuck.
I towed a 19 foot TT for several years with either a Ford E150 Club Wagon or a Dodge 3/4 ton 4X4. We went into the mountains of Montana several times, on gravel roads, never needed four wheel drive.
IMO, finding a truck you like is much more important than whether it has four wheel drive or not. 4X2 trucks are out there, but it seems they are very difficult to find!