Today is very clearly the best time to be born, so much so that I'd argue if you could choose to have kids in an older time period or today, it's borderline abusive to choose the past.
Medicine/immunization, child mortality rates, human rights, ...
https://www.thendobetter.com/investing/2018/6/7/the-best-tim...
For example the internet is much unfriendlier to children nowadays, social media is far more predatory than it used to be. The housing crisis is worse (the exact same place is nearly twice as expensive as it was when we first moved in about 10 years ago). Also, the AI dystopia and surveillance state bullshit seems to be worsening at an exponentially increasing rate.
(I say that without judgement, having been in that exact headspace myself not too long ago.)
In the lead up to the 2008 financial disaster all the bulls were saying "the housing market only goes up" without any understanding of the underlying shifts that would come to bear. It's easy to predict the status quo, they didn't need any thought, they could be replaced with a rock with "housing goes up" written on it.
For the first time in decades, risk of global conflict is rapidly rising. Two revanchist empires in the east are eager to reclaim lost territories and see their chance as the American hegemony that presided over the long peace faces stagnation & decline. This is the stuff that makes world wars. Who wants their child to live through that?
But fine, anyone can write "human well-being only goes up" on a rock.
* Appreciating what I have today
* Not fearing the future in regards to global warming, war, and other instability
* Accepting that my life could turn completely upside down in an instant, e.g. due to economic instability, war, etc.
What period of time would you rather live in, as an average person? What period of time did the average family have a better time?
But it sounds like the GP is looking to the future, and is pessimistic about their ability to do that. History doesn't matter too much here, even if I agree with you that much of history was a cesspool of pain and misery compared to these days. If people don't see a viable, prosperous future for their kids, as good as or better than their own lives, that's what matters.
Now, I say this without passing judgment on whether or not this future pessimism is warranted. Even if it isn't, what matters is how people feel about it.