Infantry warfare in WW1 would be utterly boring. Automatic weapons weren't even hardly available, except as mounted weapons, and even then they were rare.
Most of the automatic weapons in WW2 (like the BAR, and the Thompson SMG) weren't even invented until WW1 was basically over. That said, WW1 spurned the development of more effective infantry weapons -- but it never really saw them in action.
Flight Combat is basically the only interesting part of WW1, and as someone said before me, flightsims went out of style in the late 90s.
Dynamix's Red Baron 3D was the last truly great WW1 sim, and although it supported hardware 3D, it was only on 3Dfx, via 3Dfx Glide. Maybe a year later, a whole slew of WW2 flightsims got released at the same time, and all of them had mediocre sales (probably largely due to competition).. and then the whole historical flight genre basically got canned by Dynamix's parent company (Sierra, and their parent.. Vivendi?), EA (who made the Janes flightsims) and Microsoft (who made a combat version of their own flightsim.. a division which hasn't released even a civilian sim to the public in years, they finally closed the doors on just this past year).
There were some other contenders (I forget who made European Air War, or who made those cruddy WW1 competitors that Red Baron had, for example), but they were pretty minor players.
Even the recently released console versions of IL-2 are just ports of a fairly old PC game.
