I have to quibble with that a bit. The US regularly overflew the USSR and China through at least the mid 70s, meaning our best aircraft were in a very real sense fighting their best air defense systems 20 years+ after the Korean war ended.
There have almost certainly been satellite, submarine and other engagements too, they just aren't generally publicized by either side until 30-40+ years later.
True. However, I think in a real shooting war those aircraft could be attacked by a huge number of low tech weapons and get overwhelmed. From what I know about warfare often large numbers will eventually overwhelm every kind of defense. For example could an aircraft carrier handle 10000 incoming drones? I hope we'll never find out...
10,000 drones? How big a drone are we talking? They would have to be big enough to carry a weapon big enough to penetrate at least 1/2" steel (at the thinnest, only accessible from the side). If out to sea, a small EMP could drop them all.
Battles won by numerical superiority are usually won by defenders. If it's an invader, it's almost certainly early in the game. Even at the end of WW2, Germany wasn't invaded so much as it lost in France and Russia. The Allied rush to Berlin was an early aftermath. By the time supply chains necessary to conduct a protracted war have been committed, the true cost starts making invaders progressively less interested.
A more interesting concern is the major powers using proxies to demonstrate their new tech. If Russia sold Syria 10,000 drones, that might get interesting.
That certainly was true. The war was already lost when they were still deeply into Russia. the last 2 years of WW2 were just trying to fight off the inevitable.
There have almost certainly been satellite, submarine and other engagements too, they just aren't generally publicized by either side until 30-40+ years later.