Nah I don’t believe you, Ukraine has been able to close the skies over Ukraine against Russia, so Russian planes can’t enter Ukrainian airspace.
Although the Russian planes are not as good as the American, I think that whatever Ukraine is doing could be done against F-35 too.
Saab Vigen with AWAC support will probably do well enough, even against F-35. Especially if they were designed for it.
But that’s irrelevant for now, because they are definitely good enough against Russian equipment, which is what the traditional enemy is using.
If we came at war against other F-35, who would we be fighting against? If it’s USA, we wouldn’t be able to use F-35 for anything leaving us utterly defenseless.
If it’s against Russia, and Trump decides to help Russia, we wouldn’t be able to use F-35 either.
F-35 is useless, because USA has become an unreliable ally even acting like an enemy. It doesn’t matter if it’s technologically superior if it’s rendered useless by USA.
I also seriously doubt F-35 is very good in a prolonged war, because it requires insane amounts of maintenance, a plane standing on the ground because it requires fixing isn’t worth anything. And that’s a clear danger with F-35, because it requires about 5 times as much maintenance as Vigen AFAIK. F-35 is also extremely demanding in other way, like the quality of airbases. So a bombed airbase can easily ground F-35 too. Where with the Vigen you can take off and land on a decent road.
F-35 is only superior when you disregard all the downsides. Pressure the enemy to have their F-35 constantly in the air, and the F-35 air defense will quickly collapse.