This thread has veered off a little, but I wanted to add something from a very personal perspective.
In these discussions, we often hear mothers / parents saying how they knew from a young age they wanted children, and yes, it's hard work, but they love their children.
We often see the childfree/childless reacting quite strongly and negatively about children and parenting. I can see where it may come from. Women are judged for not having or wanting children, and there's a tendency to react angrily, but I notice something.
I was diagnosed with a condition as a child meaning that I almost certainly wouldn't have children, so from a young age, I convinced myself that I didn't want children, and when I thought about it, I would focus on the drawbacks of having children.
I married DH who knew about my condition, and we imagined a child-free life, we had holidays and we made plans for how our life would be.
Then, in my 30s, a new treatment became available which raised the likelihood of having children. We discussed and eventually, we decided to go ahead. Here we are with 2 DC, who of course we love very much, even though it means less time in the gym, and fewer holidays and evenings out.
The point I make, very much from my own perspective, is when I see people react so viscerally against having children ("thank fuck") is that I question where it's coming from.