Russia has used its SU-57s against Ukraine, but only to launch long range missiles from Russian held territory far out of range of Ukrainian air defense systems.
Yes, far far out of range, same way they used Su-35.
I vaguelly remember nazi drone attack on a russian airbase where apparently few aircrafts including modern ones were either destroyed or damaged. I don't count that becasue it was not a result of conventional air-defense.
Why do you keep calling the victims of nationalistic expansion "Nazis"? Were the Jews gassed by the German Nazi regime also Nazis? You seem to have swallowed Putin's lies completely, to a degree that I find hard to believe. I have Russian friends and I have Ukrainian refugee friends. They all seem to have the same view of events, roughly the Western version of events. What they differ on isn't facts. But values.
My best friend's girlfriend is Russian and lives in Moscow. She thinks Putin is great. She's a huge fan of the guy. But she doesn't believe any of his propaganda. She assumes all leaders are full of shit. She's prescribes to "might makes right" and thinks that anyone who can will attack neighbours. She thinks Westerners are naive and absurdly idealistic. She also thinks that Ukraine is as corrupt as Russia, and that Zelenskyy also just talks shit. She thinks USA/NATO also just talks shit, and NATO expansion is nothing more than an American invasion of Europe. But she doesn't think the Ukrainian regime are Nazis.
My point is that I don't know anyone, other than you, with the Russian perspective who trusts anything Putin says. That's what I don't understand? If you live in Russia, aren't you surrounded by people who continually roll their eyes at anything Putin says? I can't imagine you are in contact with that many people discussing it who actually repeat the official Putin propaganda line? You sound like little more than a propaganda parrot. I just find it hard to believe you personally believe the things you say