That's an interesting case because the collapse of the British Empire lined up pretty well with the rise the US as first one of two global superpowers and then the global superpower. It seems likely that the experience of imperial collapse might be different when you're replaced with a power that more or less is politically, militarily, economically, and linguistically aligned with you. I haven't conducted an exhaustive study, but I imagine that's not necessarily the common experience.

Of course, I would expect the experience to be different in the last three hundred years or so. Since the Industrial Revolution, it’s much more likely for an average person’s quality of life to improve during their lifetime due to technology even if their nation is undergoing a collapse in power relative to other nations.

I think people in the US, India and Australia etc are getting on ok without us. Britain muddles along.

I think "Denial" sums it up.