Re: Heinlein was a product of his time . . .

You must have met a lot of bullshit libertarians then. Libertarianism doesn't believe in AOC laws, but rather parental prerogative to raise their offspring as they see fit. And so if parents allow their offspring to engage in sexual activity, then it's simply no one else's business and not a legal matter.

Libertarianism doesn't believe in anything. Libertariansism is not a person or a group of persons; it is a broad socio-political ideology. Furthermore, you are committing the 'No True Scotsman' fallacy here by suggesting that only 'real' libertarians agree with your perspective on dropping AoC laws and allowing parents full rights over their children without gov't interference. I suspect that there's as much difference of opinion on that issue amongst libertarians as there is is amongst any cross-section of the population, only it probably does generally fall more toward the 'more freedom for parents' model (which, incidentally, does not happily coincide with the 'more freedom for kids model'--I'm inclined to think that if the libertarian model of parenting was commonplace, knowing how reactionary and protective parents are, kids would actually have much less freedom than they do now.)