I guess that you're right about depending on the definition of accuracy. But that caveat can be given to any firearm. You are also correct that they were never designed to be super accurate. One of Kalishnakov's design parameters was somewhat loose tolerances for easier/cheaper mass production and high reliability. The AK was designed to be dropped in a mud puddle or pile of sand, shaken out, but still be able to go bang reliably over and over again. It performs that function remarkably well.Depends on your definition of accurate. It is not a sub minute of angle precision target rifle, and it was never designed for that purpose.
I have asked people that told me how inaccurate my ak's were if they were confident enough in their statement to go stand downrange at 300 yards and have 3 rounds fired at them from a properly aimed ak fired by a trained and experienced operator.
No takers so far.
I'll speak to mil surp only, but short site radius with a less than ideal sight picture, varying bore diameters, loose chambers, and loose fit tolerances do not make for a very accurate combination. Custom made guns, and/or some military upgrades that have been performed by several different governments, are exceptions.
I've owned or shot several. They are fun to shoot. My SKSs were more accurate, but even that is relative. I kinda wish that I had one of each of those still, but my ARs are more accurate and functional for my use. It can be argued that the AK platform is more reliable than the M16/AR15 platform