So, that one is a pretty small sample.
I agree that kids getting into MIT are as a rule exceptional kids. I also know that exceptional kids are also being rejected from MIT and similar schools all the time.
What we can say is that being a super high achieving female already puts an applicant in a special category when the pool is engineering school applicants. When only 22% of Engineering students nationally are female and when MIT is as close to 50:50 gender ratio as any engineering school gets, it suggests that they are going further down the list of female applicants than they are with male applicants. So, a female applicant doesn’t have to be quite the same level of exceptional accomplishments as those male applicants you’ve seen. Just a guess on my part.