The 2022 Maverick has an engine literally twice more powerful than the 1962 F-100 (270 vs 135 hp). With your logic, picking on one tech detail of many, I could argue the 1962 model is "not really a pickup truck" with such a puny engine of weak towing abilities !
What this shows is that Ford merely decided to trade 18 inches of pickup box space for a second row of seat, a more powerful engine, and many other higher-end specs. Today Ford could definitely make a 1962-spec'd pickup with a weak 135 hp engine at less than $20k.
The one tech detail chosen is pretty relevant to the economic (as opposed to style) use-case here.
Being able to carry a 4x8' sheet is the difference between a productive vehicle or not for a significant chunk of the contracting tradesman market.
Sure, lots of users want trucks for other reasons where a short box does fine or a second row of seat is the winning feature regardless of box space, but the logic being applied for a full size bed requirement isn't arbitrary.
I want a full bed. As a result when I looked I was doing so in the past. Came close to buying a VW flatbed with a tools compartment built in. Thing was from the 60s.
What this shows is that Ford merely decided to trade 18 inches of pickup box space for a second row of seat, a more powerful engine, and many other higher-end specs. Today Ford could definitely make a 1962-spec'd pickup with a weak 135 hp engine at less than $20k.