Some urban legend that you need to question but it always touted up front on this forum is:
Long beds ride better --not entirely so, as stated my short bed crew cab has a wheel base comparable to most long beds.
Short beds have tiny fuel tanks. The world changed years ago. My short bed 2012 has right at 37 gal fuel tank.
I have towed fifth wheels for over 18 years now and always with a short bed. Never a slider hitch or one of those air ride ones. A regular ole Reese gets me down the road and going forward I cannot turn sharp enough to get the trailer into the cab.
A lot of it depends, but most of it are folks stating their preference for what ever reason.
My advice is to look at the specs of the vehicle and get what you need, not what I think you should have.
Have fun out there.