It is possible for the human species to exist without cigarette smoke, and doubtless for at least part of our history it did not exist.

It is not possible for the human species (or any form of mortal biological life) to exist without children.

If you want to try to define the latter observation of reality as “abnormal”, fill your boots.

I remember when I was young and edgy, and thought dunking on parents was simply sharing hard truths.

Boy am I glad I grew out of that mindset.