A lot of the effect is picking high-hanging fruit.
Like, go to phys rev D now. There’s clearly a lot of hard work still going on. But that hard work seems to be getting less result, because they’re doing things like carefully calculating the trailing-order terms of the muon’s magnetic moment to get a change many decimal places down. (It turns out that this might be important for studying physics beyond the Standard Model. So this is good and useful work, definitely not being literally stalled.)
Another chunk of the effect is that you generally don’t know what’s important now. In hindsight you can look back and see all these important bits of progress woven into a sensible narrative. But research that’s being done right now hasn’t had time to earn its place in such a narrative. Especially if you’re an outside observer who has to get the narrative of research third-hand.
A lot of the effect is picking high-hanging fruit.
Like, go to phys rev D now. There’s clearly a lot of hard work still going on. But that hard work seems to be getting less result, because they’re doing things like carefully calculating the trailing-order terms of the muon’s magnetic moment to get a change many decimal places down. (It turns out that this might be important for studying physics beyond the Standard Model. So this is good and useful work, definitely not being literally stalled.)
Another chunk of the effect is that you generally don’t know what’s important now. In hindsight you can look back and see all these important bits of progress woven into a sensible narrative. But research that’s being done right now hasn’t had time to earn its place in such a narrative. Especially if you’re an outside observer who has to get the narrative of research third-hand.