Ken,
In my view comparing aircraft from different generations is like comparing cars from different generations, some such as the Ford Edsel and the Austin Allegro were meant to be fantastic profit earners for the company etc but singularly failed. Whilst comparing market leaders from different eras such as a 1960s Austin Mini with a 2016 BMW Mini, is rather like comparing chalk and cheese, technology marches on.
I am not aware of all the contractual details between LM and the DoD however as I understand it the contract is not cost plus, LM are taking some of the risk.
I thus think that your statement that it is all the government's fault if the F35, or indeed whatever government project, turns out to be a lemon is a little wide of the mark.
A large proportion of LM's future profit stream, that will be propping up their share price and paying executive bonus etc is related to the profitability of the F35 production line, a major driver of which is the number of aircraft ordered.
My point is thus that LM's executives and Board are major stakeholders in the F35, they want the F35 to be commercially successful, unlike some of the projects that only made it to prototype stage that you mentioned.
I am sure historically that LM's profit position was not helped by the reduction in the number of F22s for the sole customer the USAF being reduced from c750 to the final 187.