A lot of it would have to do the arbitrary distinction of the "cut off" date. It's illegal for most to have sex with people 6574 days old, but perfectly ok with people 6575 days old. And even that shifts when you get into specific years. In two years, 6574 days will be legal for a little while, then it'll revert back to being illegal.
God grants one ability to consent on the 6575th day. Well, in the US at least. It is settled. What are we even discussing??