I think a lot of people think of inventions but don't have the motivation or resources to execute - and someone else creates the thing, possibly with roots deep in the past. I remember reading a magazine article (maybe in Popular Science) about the Peltier effect when I was in high school and thinking it could/should be used for cooling CPUs. In practically no time, the Power Macintosh 8100/110 came out, using such a cooler. It may not have been the first, but it was the first I was aware of, and it made me irrationally feel like someone stole my idea. A year or two later, my boss at my first job asked me to create, essentially, eBay. I read some academic articles on computerized auctions and gave it up as too complicated.

One thing that made a great impression on me was reading an old Dr. Dobbs journal (I think from the 70s) in which someone was angrily responding to Bill Gates. Gates had said that hobbyists generally steal their software, and of course that pissed people off. The letter writer said if you want to be paid for your software you should bundle it with hardware. So with hindsight, Gates became a billionaire not because he had a unique idea, but because he recognized the value of something lots of people knew and executed it.

Thinking of things is infinitely easier than sifting through all the noise and then committing 100% to making something specific a reality.

Flying is low hanging fruit, i can explain the core concepts of how it works to a 8-year old child with a paper airplane in 10 minutes. Execution is still tricky but you know that it can eventually be done with enough effort, material and machinery. AI or crypto-currencies though, is har to explain even on a high level to my computer science educated friends.

I think the final chapter, Orders of Inovation, in the original post is on the right track. Today there are less of the first order inventions but there will be more and more of the third order inventions that build upon existing inventions.