With the exception of scientific and logical terminology which have stipulated definitions, I do not believe that natural language consists of discreet meanings. So for the difference between "game," and "simulation," all we are going to find are tendencies of difference, not rules. Simulations emphasize detailed accuracy and limitations that might impede on enjoyment, games not so much, but this is not to say that there aren't some games that may have more detailed accuracy and limitations than other things we might call simulations.
However, what is wrong is to say that the above means that there is no meaningful distinction to be made between games and simulations. Most importantly, it is a useful distinction for predicting human software preferences. If you know that I like games more than simulations, then you can make accurate predictions about what I will prefer and what I will dislike. What's more, marketers study these distinctions and know that something you would call a game is going to make more money than something you would call a simulation, unless the latter has a more specific commercial purpose for training personnel.
As for Aces High, and whether it is a simulation or a game, it has aspects of both in my opinion. Insisting it is one or the other is silly. I would like to see it move more toward the simulation spectrum, but naturally there are game aspects that I wish to remain.
For the record, those who like to say, "you don't really die," also should point out that you don't really fly, shoot, or do anything in a computer simulation/game, except for simulated dying, flying, and shooting in the game.
