You 'tow' a trailer and tongue weight is lower plus use WD to adjust weight on truck
You 'carry' & tow a 5th wheel.......all pin weight is carried on rear axle (tires, axle, springs)
MFG. published MAX Tow Ratings are a misnomer and marketing hype.
"Maximum trailer weights in pounds for properly equipped vehicles with no cargo"
"Make sure vehicle payload (reduce by option weight) will accommodate trailer tongue (trailer king pin for 5th-wheel towing) load weight and weight of passengers and cargo added to towing vehicle. Addition of trailer tongue (trailer king pin for 5th-wheel towing) load weight and weight of passengers and cargo cannot cause vehicle weights to exceed rear GAWR or GVWR."
Trucks GVWR, RAWR, Tire Max Load Ratings and 'actual' payload available are the important numbers when matching truck/trailer.
