I’m not sure how comparable AI and nuclear fusion are. AI is clearly a case where new insights are needed, but fusion—to the best of my knowledge, anyway—might be obtainable via sufficient grinding. So while certainly people are still looking for new insights into nuclear fusion, one could perhaps predict how long it would obtain fusion by pure grinding. And if you expect no new insights, you would consider this a good estimate—although as you point out, expecting no new insights is probably pessimistic.
I suspect that to some extent this may be a problem of drawing the line between “grinding” and “insight”. It may be difficult to tell where the line is and these may be categories that are particularly fuzzy when one does’t yet have the details.
I’m not sure how comparable AI and nuclear fusion are. AI is clearly a case where new insights are needed, but fusion—to the best of my knowledge, anyway—might be obtainable via sufficient grinding. So while certainly people are still looking for new insights into nuclear fusion, one could perhaps predict how long it would obtain fusion by pure grinding. And if you expect no new insights, you would consider this a good estimate—although as you point out, expecting no new insights is probably pessimistic.
I suspect that to some extent this may be a problem of drawing the line between “grinding” and “insight”. It may be difficult to tell where the line is and these may be categories that are particularly fuzzy when one does’t yet have the details.