The guy shouldn't have even done so much as pushed her back. It's a college football player playing a girl(for heaven's sake). Would you punch a woman in the face if she pushed you?
Barncastle and Griner? Between two women- Griner was not right in that case either. She can't punch anyone in the WNBA and she has leaned that lesson as well.
At the risk of being labeled all kinda unpleasant things -
Objectively, just being female does not exempt somebody from retaliation. I hate seeing the simple phrase "playing a girl (for heaven's sake)" for so many reasons. I think it perpetuates stereotypes of weakness,, frailty, feminine liability. Human beings, male or female, shouldn't go around shoving each other, but, having been shoved, an equitable shove back (or the viable threat thereof) is not necessarily inappropriate: let's face it, that's the foundation for a lot of foreign policy, historically and globally.
Subjectively, you aren't talking about a defensive tackle vs. a gymnast. You are talking about a cornerback vs. a WBB guard: still a size and strength disparity, but, it ain't King Kong and Faye Wray. Let me be quite clear on this: I AM NOT CONDONING THE ALTERCATION, PARTICULARLY THE ESCALATION TO DAMAGING ASSAULT. I am pointing out that any human being, much less an athlete, who initiates a physical confrontation, much less with another athlete, should not be surprised if there is a response that is also physical. I emphasize "athlete" because physical contests are, basically, what they do.
That's not to say that there shouldn't be consequences for the actions of both parties. And, let's face it, it is highly unlikely that the initial shove came out of the blue, or out of left field. Odds are, there was some sorta sparring, verbal or "hard play" that led up to the shove.
Basically, if you physically lay hands on somebody, regardless of gender, don't act all surprised or "get the vapors", if the physical contact is returned.