> Just because someone is an adult, doesn’t mean they will always make correct decisions.

It is impossible for you to substitute your definition of correct for another person’s own when it comes to their body and their life without denying them agency and declaring yourself their superior, and in the process violating their rights to self-determination.

If they are harming no one but themselves, you have no moral basis to deny them their freedom to do so, unless you deem yourself competent to be their parent or guardian simply on the basis of that single decision of theirs, which is not reasonable by any stretch of the imagination.

> People need to be protected from themselves sometimes.

The only protection that most people want is protection from people who think this way about their lives, myself included.