Pseudonymity and Near-Minors

I'm writing an article about pseudonymity in civil litigation, and one area where courts seem to broadly endorse pseudonymity is for parties who are minors; some also extend that to parties who were minors at the time of the incidents that led to the lawsuit. But what about, say, 19-year-olds?

[1.] In some cases involving alleged sexual assaults of and by college students, courts have been willing to allow pseudonymity because of the students' youth, even though they were not minors.

[2.] Others suggest a rigid cutoff at the age of majority.

[3.] Still others suggest the cutoff would be around age 20, e.g., concluding that the age factor may cut in favor of college students "in the first few years of their schooling," but not when they are "less than a year away from being a college graduate" or even are "midway through the first semester of [their] third year at school. (Taking the etymology of "sophomore" seriously?)

[4.] And one opines:

[Plaintiff] was not a minor at the time of the alleged assaults, though she was barely past the age of majority. Of course courts should be careful not to draw a bright line between a plaintiff one day shy of her eighteenth birthday and a plaintiff one day past it. The vulnerabilities faced by minor plaintiffs do not always fall away once they reach the age of eighteen. The proper inquiry, as always, is the totality of the circumstances. However, we are mindful Doe has not presented any argument or evidence that her age raised special concerns in this case. We therefore cannot say the district court abused its discretion in concluding that Doe's age weighed against anonymity.

What are judges to make of all this? How is a judge to determine, especially in an earlier motion likely to be decided on paper affidavits, how mature, or how "vulnerable," a 19-year-old is?

My tentative view: Of course no-one becomes materially more mature on his 18th birthday than he was the day before; but courts aren't going to be very good at determining who's "mature enough" based on "the totality of the circumstances," and age cutoffs are the most sensible rule—whether as to driving, voting, drinking, consent to sex, consent to binding contracts, or pseudonymity.

On the other hand, I acknowledge that sometimes that presumption is rebuttable, especially when some case-by-case decisionmaking has real practical advantage, such as for emancipation of minors (which actually I went through back in the day). Something similar happens, much more controversially, with regard to judicial overrides that allow a minor to have an abortion without her parents' permission. Those strike me as usually fairly rare exceptions, which tend to involve some degree of in-person examination by the judge, and some concrete evidence of tangible circumstances, rather than just affidavits about maturity and vulnerability. Yet they do exist.

In any case, I'd love to hear what people think about this.