It's not angst, it's real.
Though I'm young, my work is international. I was separated from my girlfriend, apartment, coworkers, and entire livelihood in a different nation, at a position one could say I spent much of my life up to that point studying and working toward. My colleagues were separated from their families and children. Some lost their homes because they were let go from their jobs as a result. Some older friends of mine divorced because of this. Some lost their businesses that they spent their lives building. One of them committed suicide. This was a guy in his late 50s with two children and a wife, who had been forcibly separated from each other on opposite sides of the world for over a year.
Short of wars, there has never been such a brutal and absolute upheaval of population movements for civilian populations.
There are a lot of people my age who went through this type of experience, and that is one reason why I think the original poster sees more people with less joie de vivre. I am also saying it is lucky for people who just had lockdowns at home or had their lives confined to one locale or even country, or who at least had some years of "living" their lives before this happened. What I mean by that is people who at least had their 20s and maybe even 30s to build a career, life, and family, on top of their years of studying and schooling. But for those of us just getting our careers started, and for people who had international careers and lives split between countries, there were several years of nightmares along with the knowledge now that, at any moment, all this could instantly happen again.
Sure, anyone could get hit by a bus tomorrow. But it was people and governments turning on one another like wolves that was a sharp mask-off moment, especially for those of us in our formative years. That is a different type of crushing, and utterly stultifying, effect. Because it is not a random accident, but rather a cold and calculating opposition by others. All I know is that I spent my life sacrificing short-term rewards as I worked toward long-term payoffs, and as soon as I started to see results, everything went up in flames. Everything. If motivation is squelched for major life projects and milestones, I think it is clear how motivation is also squelched for personal projects or side projects. If you're older, and if your life wasn't split or shattered across the globe, be thankful is all I can say.
But for me and others in my age bracket and positions, there was this natural, sharp turn toward instant gratification, which I wholly support and understand. This is of course anecdotal, and I am not implying that it is a universal sentiment, but just offering an example to answer the original question/statement of people "working on nothing". It is because we have nothing to "work toward".