There are a lot of 1x programmers out there. So many that it's very easy to be an "above average" programmer.
I am not a 10x programmer, but I'm not a 1x programmer either. I've met people who are 6-10x programmers, and they are incredibly good at what they do, to an extent that's hard to describe. I think it requires an even balance of skill, pragmatism, experience, and passion that allows someone to have that kind of performance.
And, do you average out the productivity, or is that the minimum or maximum? I mean, if you go on vacation, you are a 0x programmer for that time you are gone.
Basically, I think it's a silly thing that's been taken to far. Everyone is a 1x programmer compared to themselves, and a 10x programmer when compared to the right person in the right context.