I've pulled GN and 5th wheel trailers with short and long bed trucks. I don't prefer one over the other as far as ride comfort or handling or maneuvering.
My current 5th wheel rv is a '97 old very flat/square corner front profile so yeah I have a old '97 manual sliding hitch for those very few times where its needed.
As others say the new gen trailers have the rounded/notched front corners that eliminates the need for a slider.
Check out the Anderson and the PullRite Superlite hitch system.....or the Reese Goosebox system.