I wonder how this could work against the F35 etc when being flown by a country with greater manpower. EG if (for the sake of argument) China could put 10-20 of these in the air for every F35, could it win an air battle?
The nearest thing in recent history might be the Falklands war, in which some Argentine aircraft were shot down by missiles launched from British Sea Harriers.
As one example a combination of Korea going hot again and China wanting to maintain a buffer state at all costs.
Vietnam wasn't all that long ago, and there's no really good technological reason that couldn't happen again.
We're also reaching a technological stage where it doesn't necessarily take two superpowers to fight a proxy war. Could India and Pakistan fight a proxy war without superpower involvement with a substantial air war component? Technologically, sure.