I think it's fine. It's a bad look, but people really don't care about it as much as they say. A little creepy for sure, but I can't persecute someone for following the law.
The issue, like the person in the responses said, is the age of adulthood. If you want to argue 18 years old isn't old enough to engage in adult relationships that's fine, but then you should also argue an 18 year old shouldn't be able to take out loan, apply for credit cards, get tattoos, join the military, start businesses, and all other decisions that have more permanent and immediate impacts on their lives.
If people think 18 is too young, they should push for the legal age to increase to 21, and live in a reality where parents are responsible for their children for longer, and military recruitment drops even further down. I'm not opposed to it.