You're allowed to want or not want whatever for your children, but as soon as they become adults, their own wants for their own life override your wants for their life. In the meantime, plenty of people (all of whom are somebody's children) have chosen to try hard drugs despite the fact that they are already illegal and demonstrably dangerous. You can't store your children in a crystal sphere for their whole lives, so it's your job to teach them as best you can and let them go. You can do the best you can as a parent and they might still choose to throw their lives away, and if they do then that's on them, not on you. Their lives are their own.

"I was a libertarian until I had children" is very funny.

Libertarianism and freedom, etc, rest upon a foundation of a well educated society with members who have enough understanding of themselves and their world to resist exploitative influences -- you are not born ready for freedom, in fact, you are born literally a baby, totally dependent for years. After years of good parenting which helps you develop self respect, values, and critical thinking, hopefully then you are ready to responsibly embrace that freedom.

Moreover, how much my perspective was changed made me realize some problems in today's society could have to do with the fact that being a parent or at least being around and being responsible for kids, was a universal fact of life for nearly all adults until very recently, but now it's possible for a young adult to barely ever encounter a child through their entire 20s and beyond. No wonder it's easy to end up with a worldview that does not account for how children can fit into it.