> "modern combat"

> have no choice

That's my point. Any battlefield today is "modern", but militaries operate with what they have. From Russia to the Houthis passing via the Houthis, we've seen insane amounts of damage done on "a modern battlefield" with anything from Cold War era equipment to cheap drones assembled by a terrorist group living in the mountains with no industrial base.

Yes, if the US wants to fight China, and vice versa, it needs 5th gen jets. Everyone else doesn't need them. They're nice to have to make your job easier (like Israel vs Iran), but don't guarantee you anything (like Israel vs Iran).