The kicker is a specialty player, and should go unharmed most of the time. But on a fumbled hike, he/she may go after the ball, and they are not different than any other player.
A 125 lb. gal getting crushed under two 350 lb. defensive tackles could be extreme, and is not necessary.
I enjoy women's sports, like volleyball, basketball, softball, etc. And skiing, surfing, swimming, where they compete against each other, on the same fields.
The two sexes bodies' are both designed and sized differently, for reasons.