It's all about the requirements, and meeting those requirements with the lowest cost solution.
I would suggest the following wording:
I have always wondered why the United States Air Force did not require the Lightweight Fighter Competition winner to be able to carry 2 drop tanks, 2 x 2k Mk84 bombs, and 2 Anti-Radiation Missiles (to suppress pop-up SAM threads), plus two radar guided missiles. An F-16 sized to meet these requirements would have been about the size of the Mitsubishi F-2, with greater range, greater payload, and, with the two additional heavy payload hard points, would have made the F-16 much more capable. This loadout will allow the Viper to perform self-escort strike without SEAD support or allow a single Wild Weasel Viper to perform both SEAD/DEAD missions.
Several notes:
1) The resulting fighter probably would not have been
lightweight. As a result, at that time in the early '70s, the program would not have survived as it was billed as "cheaper."
2) Radar-guided missiles at that time were no bueno. The F-16 was not permitted Sparrow's until the mid or late '80s as recounted by Gums and others. The reason was that the F-16 would have been seen as competing with the F-15 Eagle in the air-to-air role. That was a non-starter back then. Also... the AMRAAM did not exist at in the early '70s... and the Sparrow was too large / too heavy to mount on the wing tip rails.
Other than those reasons, sure, why not? Whodda thunkit why a company was trying to win a contract by meeting the requirements and offering the cheapest solution to those requirements?
Take an F-16, stir in A-7, dollop of F-117, gob of F-22, dash of F/A-18, sprinkle with AV-8B, stir well + bake. Whaddya get? F-35.