Are they? Did you see the picture of the chicken with three legs? Because there's no human I know who would confidently assert that chicken has two legs.
Is that at all what is being exhibited here? Because it seems like the AI is being asked once and failing.
I don't disagree that humans might fail at this task sometimes or in some situations, but I strongly disagree that the way the AI fails resembles (in any way) the way humans would fail.
If I were asked to count the number of legs, I would notice right away of course, but that's mainly because it would alert me to the fact that I'm in a psychology experiment, and so the number of legs is almost certainly not the usual four. Even then, I'd still have to look twice to make sure I hadn't miscounted the first time.