At least in my neck of the woods, road cyclists skew heavily male, I'd guesstimate 90%. Probably even higher for occupations like UberEats/Doordash, which spend all day biking and are thus more at risk of ending up in the hospital.

Update: looked up some stats/surveys, apparently cycling skews 75-80% male.

In the United States, males are known to be as stupid as a box of rocks when it comes to any sort of moving vehicle.

Male cyclists are much more prone to be doing 40mph wheelies down a blind hill in the middle of the road than woman.

Don't get me started on motorcycles, PA is just next store (we are over the border in NJ). PA doesn't require helmets for motorcycle riders, and many male riders happily throw helmets to the wind. The level of stupidity there is astronomical.

The helmet less riders are less likely to go the hospital, because if anything happens they are dead.

I assume more men mountain bike than women.