From a WW2 fighter plane engine perspective, that period's technology.
Is there a difference in the engine shutting down by running out of fuel first, then the pilot restarting it after switching to a tank with fuel. Versus, killing the engine in flight?
My father before he died was a commercial multi engine pilot and instructor. He was working on his commercial jet ticket in his 60's when he got a pace maker and grounded. For a while he flew Beach 18 for Mountain Air out of BWI. I got right seat ride alongs with him when I was home from college. During one of them he had to practice killing one engine and recovering from that. There was no blip and it was turned off nor a blip and it turned back on. That was more possible in an L19, T-41, Voyager, 150, or 172 we used to fly out of Ft. Meade. And the Storch in our game. Single engine small craft engines and their management are not as complex as the fighter engines our game duplicates. Not every civilian pilot will ever move up the food chain to multi engine, commercial, or high performance. So a certain amount of simplicity is inherit to the class of aircraft.
If you are that worried about the other guy turning of his engine, turn up your sound for his engine to 100% and use zoom to watch his prop blades. But, our instantaneous blipping off and on of high performance engines. Slightly gamey.
This post is not the way to get this changed. And being in the game, it's just one more tool in the kit to help newer players while the more clever greif each other with it. I would say an unintended consequence from the game's ease of playability balancing act.