Aces High is a simulation of WWII. Pilots saw an AC detached from a pilots persona and you and kruel think its a good thing to add name tage on enemy AC. think about it.
Perhaps you're not a real pilot. I am, and tracking real planes is tens of times easier than in AH. Why? Because in real life, you can see planes 10+ miles off. In real life, you can see markings on the planes and you can see exhaust stains, you can see dents, etc. - things that make it very easy to identify which aircraft you're looking at.
In AH, you have 6k (that's not even 4 miles) and a preset of X number of skins.
Not only that, but on real WWII planes, pilots' names were written on the side of their aircraft. Eric Hartmann, the leading ace of all time, had a black tulip painted on his aircraft so his opponents would know who he was... and he was readily and easily identified. Many planes ran when they saw the black tulip, to the point he let new pilots fly his plane as the enemy all but refused to engage that airplane, making it safer for the new pilots.
The point, is that not only did real flying in WWII make it exponentially easier to identify an opponent, but that limitations of computers and of AH itself actually make it less realistic by removing nametags than by allowing them.