I haven't read the article yet, but I think it's just harder to reach the border of human knowledge. You have to specialize hard to reach it in a reasonable time.
Sadly that makes the smart people not take general, discipline arching careers. Only in young disciplines like machine learning there is still a lot of jumping sparks for other disciplines.
Computing had been in the works since Babbage, over hundreds of years. Once the tech was in place there was infinite jobs to be had making sure humanity could democratize and exploit computing to it's highest potential.
What's coming down the hundreds-of-years pipe that we can bust open for this half-century? The 40s were famously the fighting forties, if we don't get on it we're going to be forced to take what others have in an attempt to access the infinite or stave off nihilism.
Nukes are underutilized but likely to be surpassed by fusion if the recent builds and smaller experiments pay off. With infinite computing power and orders of magnitude cheaper energy we employ everybody to do the same as before but bigger and better. Material science could unlock a bunch of new avenues for improvement. Biomed is kicking off but that's unlikely to employ everybody. I can't see it all, there's gotta be something.
Not sure how realistically viable it is, but I hope that quantum computing will bring some of that freshness back. But again, it will heavily depend on how much of it is "legit" and how much is just hype.
Sadly that makes the smart people not take general, discipline arching careers. Only in young disciplines like machine learning there is still a lot of jumping sparks for other disciplines.