I had assumed the answer was "no", and I asked the question because you seemed to insinuate that the pay gap correlates to merit, and that's why things can't be simplified to comparing people with "programmer" in the title.

Well, yes, not all programmers are the same, nor are all definitions and valuations of the title "Programmer" -- which is partly why good data on the subject of "pay disparity" is hard to come by. But I'm arguing that even in some dream world where this data exists, merit would be a very tricky variable to incorporate. As you said, programmers who are 5x, or even 2x, are not paid by multiple-of-productivity. The fact that they aren't isn't so much a reflection of unfairness, but the reality that productivity of a programmer is not at all easy to quantify, and even if it were, not at all constant.

The corollary of great programmers not being paid great wages is that there are some shitty programmers are not paid shitty wages. It's possible to accept that there isn't a pay disparity between males and females for a given job at a given company, while believing is that there's a greater tolerance for non-shitty wages to male shitty programmers.