I think youve touched on the reality spot here. As it seems with most things, people know what they know and are clueless about anything they don't, and anything else has to be crap.
My experience with comparing the AR's and the AK's has been, when you compare "comparable guns"** side by side in more realistic shooting (not your best little group shot sandbagged on a bench) they really arent all that different out to the 200-300 yards or so I think both guns are realistic. Yes, the AR has better iron "target" sights, but the AK is no slacker, if you can shoot, and as soon as you pop a decent red dot on them, things narrow down even more.
(** and when I say comparable guns, I mean the standard, issue type guns. Not the souped up, tuned up AR's that so many seem to only be able to shoot vs a basic import AK. You need to be at least somewhat realistic about things)
And as far as the complaints about ergo's, etc about the AK's, HK's, or anything "different", if people would bother to take a little time and effort to keep their continuing education going and learn as much about as much as they can, they would see that most all the different guns work well and about the same, and shoot reasonably well (assuming you can shoot) if you run them as they were meant to be, and not the one gun you like and swear by. You need to spend some quality time ith any of them to figure things out and how best to work them.
You always hear basically the same regurgitated complaints about this or that, and those complaints usually come from those who have no real experience with what it is they are bitching about. And to take that to another level, you get the complaints the gun is bad/no good, because its an enemies weapon and someone shot at them with one.
People really need to get out more.