OTOH, if Ukraine had F-35s, it probably wouldn't need to spend a year and a half preparing a covert operation to take out bombers that were conducting regular attacks on them, either, they'd just intercept them in the air.
Besides that, I doubt the US would have ever sold a single F35 to Ukraine just because of revealing radio-emission and reflection patterns to russian air defense, basically drawing F35 useless for future usage against Russia.
That wasn't really the subject of discussion, though.