The F-35 was not built for dogfighting. It is supposed to sense and launch long before the opponents are even in visual range.
The very same hubris caused trouble in Vietnam, which were fixed with rapid re-introduction of guns to fighters, and dogfighting to fighter schools. Sad to see this lesson having been lost.
There's a difference between the classic definition of BVR meaning slinging a missile at a blip no one has seen 30 miles away, vs the F-35 concept which is to have excellent sensor suite leading to the pilot having excellent situational awareness so the pilot can shoot down the other plane before the other plane knows they're present, etc.
Its tricky to get into visual range to visually identify the target as a mig-21 and not a 767 full of civilians without at least some dogfighting performance.
And that's not even getting to the part that the only reason why L band can even detect F35's and F22's is because that they have features like vertical stabilizers which are too small relative to the wavelength. B2's and B21's do not have this issue.
Finally the idea that one F-117 shot down somehow invalidates that fact that the F-117's stealthiness provided it protection with 99% effectiveness is absurd. The reason why it was shot down was because of USAF's arrogance in flying identical flight paths day on day and a SAM operator realizing this and succeeding in targeting it the moment it opened it's bomb bays, when it's stealth was degraded.