Ideas aren’t getting harder to find

I agree with the author. Here is inspiration for all of those problem solvers out there:

https://uia.org/encyclopedia

I want to be as optimist as the author. But it's hard to not believe the existence of a "low-hanging fruit depletion" dynamic in science, at least the hard sciences, to some degree. At least the material and equipment costs tend to go higher.

... but maybe harder to implement.

Dark Matter is so mysterious not because people don't have "ideas" about what it could be, but rather because it is so hard to detect. All of the other big problems in fundamental physics have this issue.

Maybe it it is not so bad outside physics. I remember people talking 10 years ago about how the drug industry had run out of "blockbusters" but lately we've had mRNA vaccines and Ozempic.