Flying airliners in one straight line, I guess you wouldn't get that. Not many would. However, simulators provide substantial training for aspiring pilots and protocols in the real world. .. as has been mentioned. Second, the combat flight simulators also provide the fun of "killing stuff" while maintaining the realistic aspect.
Just recently released is the "DCS Black Shark" helicopter simulator. An incredibly realistic virtual representation of the Russian Ka-50 helicopter. You can compare it to Falcon 4 on the level of complication and realism. There is a 6 minute video tutorial on "How to start your engine". You might wonder "where the **** is the fun in that?!". The sense of accomplishment really plays here. It is so complicated
because it is so realistic, not because the developers decided to make complicated stuff up.
If you always wanted to be a Fighting Falcon/Viper pilot, or a Black Shark pilot, but never passed the qualifications for the airforce, or financial issues, or whatever.. this is your best bet. And the cheapest. Though a set of Track IR 4 and a good HOTAS setup will go a long way, as well
I play Armed Assault (and OFP a few years ago), because I have interests in ground warfare and the military. I once thought of joining the KCT, but eventually decided it'd be a little bit too dangerous for me (and was well on my way through qualifications). Armed Assault is the closest to what was once a "dream". And it isn't only a matter of "killing stuff".