I asked this of three highly respected Division 1 coaches at an NFCA Coaches College course over a year ago and there was a somewhat awkward tension in their responses. I came away thinking that it was at best at least an issue for those coaches. At the last course, however, I got a different response from former and present Division 1 coaches, so perhaps the college staffs are coming around.
As I've mentioned once in awhile on here, many years ago (I think it was 2003) I watched an Ohio pitcher take one back to the face in a tournament in Alabama. It was a SHOT hit by an extremely talented athlete. The hitter and her mom were in tears. I, as at that point a pitcher's mom, nearly vomited. Fortunately, the injury was so bad that the Birmingham hospital told the family that the plastic surgery could not be done until the swelling went down. I say "fortunately", because that meant the plastic surgery was done at OSU and within six weeks, there was only the faintest scar at the top of what had been a smashed cheek bone.
Ever since that day, I've felt that if a kid wants to wear a mask, that is her absolute right and as far as coaching goes, it would NEVER be an issue for me.
But old habits die hard. Even after seeing that injury, my DD completed her career without wearing a mask either in the circle or at 1st; she made it clear she didn't want a mask, and even to this day she might make some kind of soft crack when she sees players wearing them. Looking back, we should have required her to wear one, at least during HS/Travel Ball. We dodged the bullet.