Ruwart and LaBianca are right: you define an age range starting a bit after puberty and ending a bit before 18, and say that the rebuttable presumption of ability to consent changes as you age through that range. I and others said this within 24 hours of the controversy erupting, but it took Ruwart a week to get on board and step back from the notion of age-blind rules, and both she and the LP suffered somewhat as a result.
We still don't know who in Ruwarchotopia would prosecute parents/guardians that pressure their pubescent children into sex(ual commerce), but the LP's anarchists never really tell us how the weak and helpless would be protected in anarchotopia, so that's not news.