I dont think BF2 or any games are close to an authentic war zone. They are full of gameisms. Like people standing in the open firing. Being perfectly accurate, when moving. Snipers are able to use rifles standing with perfect aim.
With vehicles they are more unbalanced than they would be in real life. You cant get lucky shots, which take out systems. Basically if you hit a chopper with one bullet then they would get the hell out of there unless the mission is really important. They arent bullet proof at all.
You jump into them and you are invulnerable (for the most part). You jump in and out instantly, no set up time almost. Infinite bullets perfect, targetting etc(allies are cleary indicated).
There no where near close to making it a combat sym. I just think they should be clear about what they are doing. Lots of unbalanced things and problems would go away if they really made it a sim.
I dont have anything against vehicles as long as they keep them balanced and forget real world emulation.
Team Fortress 2 is the obvious example of a balanced infantry shooter.
Its probably all moot anyway as vehicles do usually fall quite easily in Bad Company2. Except for in the large map areas and I've heard that the vehicles are more armoured and powerfull.
Also another thing they never take into account how the majority of the game will be played. Clans have to come up with all manner of rules to make it balanced and seemingly fairer. In random matches they give all the means and advantages to the few to be able to troll the many.
Sounds like you need to play arma 2 not Battlefield then, personally I have done infantry combat to death from years of gaming and prefer vehicles in combo with infantry as it makes things more interesting and semi-realistic, also (back to console bashing) the main reason why many fps are infantry based is that consoles don't have the technogoly to generate large maps and vehicles rather than gamers actually wanting infantry combat only. Anyway each to his own I suppose but when I use to play bf2 I rarely went on IO servers, I just found it a boring nade and claymore fest.

(and then usually end up humming the bf2 theme music
)
, give us something new damn it
suffice to say I ended the round 26/0 K/D with 4 tank destroys and 2 nemesis pins on a pair of medics who kept suicide charging me