Men and women tend to have different breathing patterns notably on fly.
Conventional wisdom is not to breath on 50 m freestyle as it isn’t a physiological requirement. However i’ve seen a few elite womens races where the eventual winner grabbed a breath around 20 m out.
https://www.youtube.com/watch?v=GvJZi8lIpvIWomen's 50m Freestyle Final 🏊🏻♂️ | Tokyo Replays – YouTube
I’m wondering if their is a psychological effect where taking a breath creates a comfort and enables the swimmer to power on without losing technique so taking that one breath is on balance worth it…