The concept was to couple a sophisticated flight-sim engine and a sophisticated terrain engine and use it to drive tanks, infantry and boats too. It was way too ambitious for the amount of money they had, and so they released the game without a ton of the features advertised. I can understand why people are angry. At the same time, if you want a game of this type at all, WW2OL is your best hope of getting one (and don't tell me that OFP or MOH: AA are similar, since they don't have the huge arena and huge numbers of players participating). No publisher is going to commit big bucks to a sim-oriented project nowadays, so the shoestring approach CRS took was the only way to get it done. If you want them to fail, it means you only want to see games just like the ones that are already out.
P.S. 400 players peak is B.S. At peak times they regularly get 1200+ players. They don't give player numbers, just percentage of capacity, but if you use your head you can determine the capacity from the fractional part of the percentage and determine the number of players from the capacity.