I've read many accounts of the lives of mostly hunter-gatherer tribes living far more care-free and convenient lives. Yes they had no way of treating most diseases, facing natural disasters, and preventable deaths, but from what I understand the reports of scarcity and constant danger are far overblown, at least within certain periods.
I personally feel "happiness" is more correlated with agency (or at least perceived agency), and in that measure civilization has been regressing since the industrial revolution. The amount of long-term planning required has increased and it's less possible to live "in the present", moment to moment.
Wasn't the whole point, to get so good at things we got back to that eventually? I don't even understand what the point/goal/target is anymore? Like we forgot society should be getting better every year. Or it used to be the conservative towns that had beautiful tree lined streets, but now it's conservative to NOT plant anything for the future. What is it all for at this point?
Survivorship bias. All the corpses aren't here to tell us anything. Just 100 years ago, most parents would bury at least one of their infant children. People back then were tough, because the physically and emotionally weak died off. Humanity's "natural state" is like the animals, to kill or be killed, to wage war, to reproduce, to die. The difference is we have a big brain that strongly incentivizes us to try to leave that world behind. Its not perfect, but we've improved in basically every measurable way on the scale of our species.