As if that was the reason.

Also, I've seen a great deal of adult babies in academia, so let's not be ageist here.

I suspect the reason is not about babying her as much as it is a concern for her development, about whether she would be "missing out" on the opportunities for social and intellectual growth in college. This kind of thing is usually why well intentioned higher ed people put roadblocks in front of precocious young people.