Step out of the 20th century, and step out of the closed "flightsim community" mentality, and try to look at the world. To the newer generations, visuals and graphics are an intimate part of what constitutes the overall reality of a game. To them, the word "realism" is never complete without the visual aspect of it, and a "game that has good FM but lacking visuals" is just not going to cut it.
When a certain game has some very inspiring, realistic graphics, it is more than likely the player would be satisfied by it alone, despite lacking realism in the FM department. People don't just start appreciating the 'realism of flight modelling' right away. It is only after one has given enough time and experience in enjoying a game with a 'realistic FM', that they finally begin to accept the wonderful dynamics of thrilling, realistic aerial combat, instead of the point-and-shoot arcade game.
And, how are new players ever going to learn the joys of such realistic FM when they don't find the game intriguing in the first place?
It's not as if our community is going to play AH forever. How longer can we play this game - 10, maybe 20 years before we go too old?
If a game is going to survive, it needs a constant supply of new players - and we should try to understand that many of those new players, don't necessarily think in the way we do - the old, vets of the flightsim games who used to play when everything was in black and white, and the concept of 'graphics' wasn't even born yet.
To the newer generations, what they see is what they feel - and if what they see is lacking graphics, then their gaming experience will also lag behind.