So your anecdotes can beat up my anecdotes?
You're being silly, defensive and pedantic. Because you claim not to have experienced these rampant issues, or have the free time available to coordinate with groups of trusted people, in no way whatsoever invalidates any of my experiences or assertions.
I have around a thousand combined hours between Left 4 Dead and L4D 2. Hundreds in Arma, DayZ, Battlefield, Bad Company, and around half a dozen others going back to the MSN Gaming Zone days on dial-up.
I've been around the block.
You simply cannot refute the fact that in MP your fun is still largely dependent on other people making the experience worthwhile, and if you're someone who doesn't have hours on end to devote to finding the right group every night, sorry, it's still a crap shoot. I can't TELL you the number if times in L4D, an older CO-OP game, it has been ruined by a TKer suddenly turning and gunning everyone down inches from the safe room door. Or "nerd generals" incessantly trying to order everyone around, and then getting audibly upset when things don't go their way or someone doesn't follow orders.
And don't even get me started on DayZ.
Sorry, my time is more valuable than that. If I can prearrange a game with steam friends, sure, more than likely we'll have a blast.
But your asinine assertion that these things just don't happen is only trumped by your saying that all single player FPS are the same.
If that's your preference, fine, more power to you, but bombastically attacking anyone who points out experiences that contradict you aren't winning you any arguments.