The truth here is both the F-22 and F-35 are truly outstanding aircraft tailored to different defense jobs in the future. The Airforce wants to reinvent their winning F-15 and F-16 one two punch for the 21st Century.
Cost drivers are the development of the electronics. What needs to be done is a fusion of the electronic systems to allow the F22 to be retrofitted with a higher performance system bus and allow the F-35 to piggy back on some of the unique capabilites of the F-22.
The F-22 digital bus is largely 1980/90s computer technology which is way out of date. It can do amazing things but it could do even more amazing things with better computers which the F-35 has and be much more supportable going into the future
The F-35 could potentially by streamlined by using some F-22 technology. This is complicated because the F-35 technology is intentionally dumbed down, with a lot of re inventing the wheel to keep F-22 technology from getting transfered to other countries.
I would argue that it is far more important for the USA to re invent it’s world beating F15/F-16 hi-low mix concept in the F-35 and F-22 and deploy enough of them to make a difference than it is to keep secret a lot of technology that our adversaries probably have already have gotten in far greater detail from espionage.
You cannot hold the wind in todays internet driven world so we should not try to do the impossible. In todays world you simply have to out run your competition so we need to get our hardware deployed as quickly as possible and provide a solid foundation for future upgrades to always keep our qualitative edge as great as possible.
A certain degree of cross platform compatability and integration would allow for this without giving away a store which probably already resides in the hard drives of number of our adversaries.