It's not that I suspect that he'd advanced a lot since his last presentation as a woman, so much as it's possible that he advanced a reasonable amount during his time as a woman. So Barbara's body of work includes some junk and some good stuff, and Ben's body of work includes a small amount of good stuff. If you aren't thinking very hard, it looks like Ben is better than Barbara from that.

I do agree that sexism is a plausible cause; I just compulsively look for alternate explanations for anything.