It's not the act, it's the motive. I've whined and complained, but I'm getting over it as I realize the difference between a war and the MA.
In a real war the motives are
1. Complete your mission
2. protect your squadies
3. Kill the bad guys.
If everyone motives were these three, behavior in the MA would be very different. But....
In the MA the motives are
1. Get as many kills as you can
2. prove you're a better stick than everyone else
3. land your kills
4. help a squaddie if he asks.
5. take a base or some other mission based task.
Most of the trash talking on 200 seems to involve MA-motives 1 and 2. The guys looking to score kills are always picking because it's easy, but the guy who gets picked thinks he was robbed of his opportunity to prove he was a better stick than the guy he was fighting.
Let's face it, taking bases and winning the war means nothing to most of the people in the MA. So motives 1 and 2 drive most of the behavior. I think this is also compounded by the idea that some believe getting lots of kills proves they're better sticks than everyone else. This leads to everyone having to jump on 200 to tell a picker he has no real skill, just in case he was thinking the kill he just scored was leading him to believe it. Once you understand that, the whining is predictable and avoidable if you choose. Also, once you understand that, it's easy to ignore.