This study seems particularly flawed to me just due to the fact that, provided you have Phantasia on hand or if you don't mind buying one, you can change gender on a whim. Also because, as others have stated, just being a tank or a healer gets you the lion's share of comms, as it were, so gender doesn't really play into it.

This character has existed since around 2.4 or 2.5, has 1,376 coms, for the most part has mained MCH, and has never gender swapped with a Phantasia, if this helps.

Most of the time I never even notice a character's gender, I just comm based on how they play or act.