Despite the fact that I've always wanted kids, right now I'm not so sure. Just look at the things happening in the world.
I imagine that this argument has existed since time immemorial. I can just imagine some ancient roman saying "But is it wise to have children now? With the barbarians coming down from the hills?" or an american couple in 1860 saying "I can't imagine bringing a child into a society that keeps slaves, that is more than likely to be ripped apart by war". The decline of society at large and it's suitability for future generations is an ongoing argument, likely never to end.
It's a complex, highly personal decision. It is at the same time one of the simplest. You do it, or you don't, and you live, and live with, that decision for the rest of your life. It's one of the most rewarding, joyous, terrifying and exasperating jobs you'll ever have, parenthood.