My point is, at large companies with lots of very competent developers (I've worked at two of these: Salesforce and Twitter), 10X developers are not a thing on any useful metric I can think of.
The places I _have_ seen someone be 10X better than the people around them has been more a function of the people around them (their overall ineptitude) vs that individual.
Sorry, but the only places I've seen 10X developers is when there are lots of 1/10th developers around to compare them to.