Yes, it means that they are not biased against non-binary people. If that's how some of the songwriters identify, and they are doing statistics by gender, of co

Yes, it means that they are not biased against non-binary people. If that's how some of the songwriters identify, and they are doing statistics by gender, of course they would include it. In any case, omitting those songwriters or arbitrarily assigning them to the male or female category wouldn't change the conclusions, because there are only a few of them.