It's always been financially complicated for most people. The notion of a nuclear family prospering with a single income was mostly only possible for a limited slice of the US population during a few decades post-WWII. If you take a broader historical view that was a brief anomaly.

And it's really weird that anyone would think of something amorphous and uncertain like climate change as a reason not to have children. Even the unlikely worst case scenarios are still going to have less impact than the major wars and plagues that our species has lived through. Some people just lack a sense of perspective.

...and all this is only true for the last few hundred years of "belongingship" / capitalism etc.

Dense population creates all this, in reverse without dense civi you wouldnt have all the gadgets we have today :-D