oh my! For these supposed upgrades, within what is referred to as "F-35 Block 4"... per the U.S. Government Accountability Office (GAO), no business case, no baseline cost, no scheduling estimate. I guess, after the decade+ F-35 debacle... go with what got you there/here!
Yes, there were management issues with the development of the F-35. And yes, there will probably be management issues in the future. Yes, there were excessive delays and in some cases cost over runs. It would have been great if they didn't have those problems, but its a big government project, and those are always going to have problems.
The important question though is not "what mistakes were made in the past", but "what is the plane like now/what can it achieve".
I would much rather have a plane that had dozens of delays and other problems but ended up being the best in its class, than a plane who's development went completely smoothly, but at the end of the day ended up with inferior performance/technology/etc.
I think the F-35 is a better plane than the Gripen/Super Hornet/etc. not because "gee wiz, its development went so smoothly" but because "This thing has some features that make it superior" (even if it was much later than expected).