There is a lot of value in having wings of "old" planes (i.e. - planes that are not very modern, not very expensive stealth fighters). Air National Guard doesn't necessarily need stealth, especially when alternatives like the F15 are relatively cheap and remain incredibly combat effective.
The F35 has been plagued by having far too much demanded of it, I think. I've read a lot about the plane - the development, requirements, use, etc. Having three distinct variants already separates from the original mandate for one plane to do everything, for example. The military simply wanted the impossible and the time required to develop this mystical plane necessarily takes so long that the requirements change substantially by the time they get even halfway through.
But even if the F35 gets classified as a failure (I don't believe it is, but I'm far from an expert on this), the technologies it pushed and integrated are insane. The substantially expanded fly-by-wire frees pilots up to concentrate on mission. Data connectivity between planes substantially improves radar projection and reduces the need for larger, undefended AWACS (not replaces, but reduces). The integrated camera/helmet view gives pilots better visibility and awareness than any plane before it. It gets something like 2/3 the thrust of the Russian SU-57 with only one engine (our engine tech has always been a decade or two beyond theirs).
It's a tremendous fighter plane that faced an impossible set of development requirements and still met almost all of them. Of course there are going to be frustrations, setbacks, small failures, etc. But holding each one of them up and declaring the program a failure is myopic. And this is also, I think, technically one of two all-the-way 5th generation fighters as the SU-57 and Chinese J-20 cannot super cruise without afterburner. (though that is up for debate and the Russians reject this as a definitional aspect of a 5th gen fighter).
