I wonder if part of it is that symptoms are sometimes very different in men vs women of a heart attack.
Also, I think people seeing a man hit the ground immediately think heart attack. Seeing a women hit the ground, people think faint, vertigo, blood sugar, any number of things before thinking heart attack.
This is about cardiac arrest, not heart attack. Heart attacks, AFAIK, don’t benefit from CPR, while cardiac arrest requires it.