They may be poor but overall, they are almost certainly doing much better than the poor in the past. I believe what OP is referring to is that people think in

They may be poor but overall, they are almost certainly doing much better than the poor in the past. I believe what OP is referring to is that people think in relatives such that they compare how their life is to others/the past. With no bad wars in most countries recently to compare against horrific times, everyone is comparing themselves to everyone else's life hence making them unhappy despite the good times we actually are having nowadays. This also somewhat aligns with the many studies showing some of the downsides of social media.