Not really.
First, because “libertarian” and “socialist” aren't opposing poles (libertarian socialism is a thing), and, second, because non-libertarian socialists aren't particularly against (or for reducing the age set in) age of consent laws. And, third, even anarchists, who are the polar extreme of libertarian socialist tend to support age of consent laws, there only consistent opposition to current ones is, as with other laws of current societies, objection to the structural basis on which they are made and enforced, content of the laws aside.
EDIT: Similar things may also be true of libertarians not being as anti-age-of-consent as portrayed as I have noted about socialists; I have had somewhat more contact with broad leftist communities than broad libertarian ones outside of their overlap, so I may be more susceptible to misestimating the prevalence of certain views in the libertarian community because they are highly visible when espoused because of how transgressive they are.