No, I don't think the choice of examples is bad - I had another draft where I used understanding the pathogenesis of some common disease as an example, which is even more clearly beneficial.

My point is that even when rational analysis tells us that something will be very useful, the "sense of curiosity" can disagree. Otherwise, we'd all be fascinated by immunology because of its high probability of giving us a cure for cancer and AIDS. Likewise, discovering that Stonehenge was built by aliens would be practically useless unless it provided some way of contacting the aliens or using their technology, but it would still be considered "interesting".

That's why I didn't include "gives a practical benefit" as a criterion. Instead I said "changes a lot of beliefs", which a better understanding of photosynthesis wouldn't, and "teaches you something that other people want to know", which photosynthesis again wouldn't (lots of people would want the improved solar technology, but not many people would care how it worked).