Stewart has a great rant anti rose tinted specs.
It's an evolutionary thing (that's my answer for everything) that we baseline against the first thing we see. If we didn't we wouldn't be able to cope. It'd be "Television! Wow!" and "Fuck me, aren't lorries brilliant?" but actually I take for granted what amazes my mother. So: I'm upset because a bunch of whales got killed; people were just as upset that a third of Europe died in the plague (more or less). And we look back and see that yeah people were unhappy about something but that something was so much worse than what's going on today so actually our ancestors must have a lot happier to begin with.
It's false of course. Context is everything. (But isn't sliced bread simply the best thing ever?)