From a societal standpoint, the lack of children is harmful on quite a few levels. The obvious is the lack of population growth, and an aging society. But the issues that stem from that are pretty serious. On the top level, most of millennials won't be able to experience retirement like how the boomers are, as there isn't enough young people to support the aging population, and few millennials will 20mil in the bank when they reach 65.
On the other side, the GenZ and future generations are inheriting a world that's been ravaged by rampant consumption, and they themselves don't have the numbers to do much about it. Entire towns are being abandoned with the environments around them being left as messed up as ever because nobody is around to even notice that abandoned factory from 30 years ago had tons of toxic chemicals left over when the company left the town and never got cleaned up. And even if it is noticed, the potential to clean any of that up is evaporating as there's just less people to do something about it.
And that doesn't even get into how there's fewer people doing essential jobs. And I'm not just talking about the blue collar void. Do you remember how much the farmers were complaining that they didn't have enough hands to harvest their crops during the worst of COVID?
Hell, I've seen entire neighbourhoods that's had help wanted signs posted for more than a year straight. We're already starting to see the early onset of labour shortage, and Canada's one of the few top tier countries that has managed decent population growth thanks to our immigrants. Imagine how bad it is in Europe and East Asia?
That said, from an individual level, the governments, on every level, are really failing to create an environment where people can decently have children in the first place. When you work full time and constantly worry about making your bills, you have significantly less leeway to think about something that'll add massively to your payments.
Even dating is difficult under those circumstances, not to mention hookup culture that basically treat long term relationship as a thing of the past.
Marriage, and then having a child instead of a pet? Forgettaboutit. Not when a significant percentage of the population is already living paycheck to paycheck. One wrong move, and they're heading right into bankruptcy. Not the sort of environment to have children.
