laws keep law-abiding people under control

If there were no AOC laws or similar social mechanism in place, the number of Jr. High and young-high-School-aged girls dating or sleeping with young men 4-10 years older would go way way up, and with it probably the number of teen pregnancies, particularly among those dating mentally-immature-for-their-age college-age people.

Whether this is a good thing or bad thing I do not know.

As for under-18 girls and young women sleeping with men over 10 years their senior (particularly girls or young women who haven't graduated high school or completed a GED) who aren't their husbands, that wouldn't change much* because even absent laws, there is a strong social stigma at least in the USA and its cultural clones - a stigma that keeps most people over the age of 30 from dating girls or young ladies that young.

*in some social or cultural circles where there is no such stigma, the incidence would rise just as it would for college-aged men.

There is also the issue of informal child prostitution or child-swapping, where a girl is coerced or forced to have sex with another man for payment in cash, goods, influence, maintaining a friendship, or even in-kind-exchange with another parent, by her parents. That happens occasionally now and if the AOC laws were dropped and prostitution laws weren't refined to make it clear that "encouraging" your daughter to have sex with anyone you stood to gain anything from, financial or otherwise, was a severe crime, this would increase some. I say some because the vast majority of parents would never consider doing such a thing under any circumstance. "Civilized" people in America do something like this by semi-arranged marraiges, making sure their daughter has ample opportunity to fall in love with a man with the "right" connections - in effect "bartering" off their daughter for future financial and other gain. Unlike a true arranged marraige the girl not only gets a veto but gets to squelch the deal early on if she wants to.