> “Our frustration is greater when we have much and want more than when we have nothing and want some. We are less dissatisfied when we lack many things than when we seem to lack but one thing.”

I think the elephant missed here is the focus on what we have or do not have instead of a focus on what we can attain. Mass movements are created and accelerated by the thought that things can be achieved through them. Regardless of how much you currently have, a mass movement is appealing if it offers you hope to get things you otherwise couldn't. If you think violent revolution will bring you immortality, that's a "pretty good deal" and you might want to take it. It's no surprise that many religions heavily depend on this for controlling and gaining followers.

Being limited by your imagination, I think, is the driving force behind "your situation improves and then you revolt." Your situation improving can transition you from a hopeless "this is always how it will be (suffering)" to a "hey, things can change" mindset, which allows you to hope for and potentially even fight and die for a better future. It doesn't matter what you have, it matters what you can get.