"if you make inferences from the number 16 and its relation to development the concern is plainly to 'protect' the girls to a greater degree than boys."

I don't make inferences from 16 because it isn't an option. I know people who were granted adulthood at 18 because adolescence ends there ( for boys. ) And I know people who were Bar Mitvahed at 13 because puberty begins there ( for boys. )

If we were to recognize female biological hallmarks, then the girls would arrive at 11 and 16 respectively. ( Note, Soleil Moon Frye had to wait on her breast reduction surgery until 16. Surgeons pick that age so that they are working on already grown adult breasts and not those of a growing child. )

Either way, Feminism begins with a rejection of Patriarchal protection which keeps women from the vote, from owning property and from sexual self-determination for their own good. They can be just as obsessive as any others over child-protectionism, but since their adulthood starts earlier, delaying it to make Men the measure of adulthood ought to be rejected.

And even if one were to shift it "conservatively" to the latter end, then they'd be replicating the reality of American marriage for so many in the past; whole lot of 18 year old male adults marrying a whole lot of 16 year old female adults. But there marriage was seen more as a civic virtue than as a purely selfish emotional choice. And as marriage ( and childbearing ) rooted the young to adult responsibility they were the hallmarks of the onset of adulthood.

I would hope that even if a Woman chooses not to marry or have children, that she doesn't choose to delay adult privilege in deference to Men.

Dante