There's a different side to consider in all this.
1.
WW2 lasted for 6 years from 1939 to 1945. From a technological standpoint, 6 years is a long time in research and development, and the technological gap between early war aircraft and late war aircraft in varying fields ranging from ergonomics to automation, is very wide. Contrary to what colmbo said, automation in plane management was not common, and it took considerable amount of high-grade technology to come up with a system that warrants minimal human management. In combat, a complex plane to manage may even result in deaths, as can be seen in many existing AARs on how an unseasoned pilot came close to meeting his maker, because he made a mistake.
In this sense, it can be said that what kind system the plane is equipped with, is as much a combat factor as its speed, climb-rate, or turn radius. Thus, in principle, more complex forms of management can become another excellent material to depict in a combat simulation game.
2.
The problem is in coming up with a generic, simplified form of management that can depict some of the basic (but also important) differences of individual planes and their on-board systems, and yet still easy to comprehend and use for gaming purposes. Obviously no one wants a 20-step checklist just to take-off, or remember the sequence in which they fiddle with pitch and throttle levers so they don't over-rev and blow out their CSU everytime they adjust speed.
Many AH gamers frown at the concept of "engine management", but it doesn't have to be all that complex. The whole "complexity" bit is fairly relative; players of some other games with more relaxed realism in plane handling consider AH a very complex and difficult game to play. When I came over to AH from Fighter Ace, learning to learn the limits of flaps, using the hook to land on CVs, switching between fuel tanks, learning the weapons selection system, learning to use hat-keys for views were all very "complex" to me, until I got used to it. Its basically a matter of getting used to.
3.
A worthy comparison might be made with the IL-2 series from 1C:Maddox. IL-2 has its vices for sure, but there are some very compelling strengths to the game, and one of them is the concept of "CEM - complex engine management". This is a very clever use of words, since IL-2's "CEM" is in reality, anything but "complex". It's basically a very generalized, simplified form of engine management system which is divided into 3 major parts - throttle, pitch, and mixture, coupled with some additional systems that deal with superchargers, radiators and etc..
People who are used to AH, and never played IL-2 think that "CEM" is a needlessly complex form of realistic depiction. But frankly, learning to use the CEM is as about as complex as learning when to drop down flaps during combat - you essentially memorize perhaps one or two more factors in game, and just press the keys accordingly.
In many cases, the mixture control is rarely used under normal circumstances. Only at very high altitudes where the air is so thin, does anyone need to fiddle with mixture control. In German planes, the mixture control is automated through the use of Kommandogeraet, so there's no need to use it at all. Prop pitch control is hardly ever touched, since most planes use CSU. The only thing people really use often with IL-2's "Complex Engine Management", is like in AH, the throttles. In some planes the supercharger has to be set manually, in which case all you have to do is memorize the altitude range you have to kick in the supercharger to next gear.
Essentially, in most cases IL-2's CEM makes you push just one (that's right, one) more button during combat.
4.
Then what's the point of "CEM" in IL-2?
"CEM" is an illusion - a cleverly implemented device that gives out a feel of complexity and realism. It's an immersion device, which apparently works so well in achieving its goal, AH gamers think that IL-2's plane management is more complex and realistic than AH, when in reality its not. Unless you completely forget to shift to next supercharger gear, or forget to thin mixture when flying at 30k, the planes mostly perform no better or worse than in AH. The workload befalls to the pilot in IL-2 and AH2, is about the same, barring perhaps the use of one or two more keys.
This is plain ingenuity - they made a system that uses 1~2 more keys than AH under normal circumstances, and immediately, it gives out a powerful feel of immersion despite not being all that different. This, IMO, is something AH can use. Instead of just outright refusing everything, a small compromise such as the "CEM" can change how people perceive the level of realism in AH, without changing anything much in reality.
Think of it this way:
Just how "difficult" will AH become when it is equipped with a CEM exactly same to that of IL-2?
1. The La-7 pilots will have to press one key to shift superchargers at high altitudes.
2. Many allied planes, such as P-47s or P-51s, will have to press one key at very high altitudes to thin the mixture out.
3. German plane pilots will have to do neither - they've got Kommandogeraet. They can perhaps gloat about it.
Practically, this is about it. There are some other methods in using the CEM, but its effects are minute at best. A very small change, which brings out a big illusion of immersion.
