One more thing to react...

Someone pointed out that WWI planes are so primitive that it is possible to simulate them better and quickly, and WW2 planes are so complicated with their CEM and other stuff, that it takes years...

What about DCS A-10? If your argument is correct, we should not be able to fly it, because it would be still in development... (MG spent already 7 years on WW2). Based on your argument, I would expect simulator of A-10 around 2035...