Anything that takes work required some form of motivation. It is very likely that the person that did the thing you think to be wrongheaded was a lot more like you than different from you.
The times when experience gets in the way is when the reasons for decisions are no longer true, but you fail to revisit those decisions. My favorite example for this is the Jet engine:
Radial-flow compressors create far too much drag to create efficient engines. Axial flow compressors generate too little compression in each stage to create lightweight engines. Therefore jet engines are not practicable.
The above paragraph was true around 1930. Improvements in metallurgy, machining, and compressor design eventually made axial-flow compressors much lighter and more efficient. I can easily imagine a more experienced engineer telling a less experienced one something like "I looked into that and the math just doesn't work out."
One can't fault the more experience engineer because one doesn't have time to reexamine all of the underpinnings for all of the knowledge one has about the world on a regular basis. Though I do recall hearing a few people (including Feynman) who would keep a journal of problems they failed to solve. Any time they would learn a new technique or about a new technology they would flip through and see if there was anything in it that could be solved with the new information.
Common Lisp has found a very high local-maxima for macros. If you knew all of common lisp except defmacro, I could explain how it works to you in about 3 sentences. This is an absurd lever for how much power it gives you. This is also where many "lisp-in-foo" implementations fall down.
They (rarely) use the scheme macro system (which has a very complicated algorithm behind it) or more commonly implement the common lisp system, but without the features of common lisp that make it reliable. A major exception to this rule is Clojure.
I'm not a huge clojure fan, but every single place in which it differs from common lisp, it is immediately apparent that Rich understood why it was done in common lisp, and has very good reasons for doing it differently. It's one of the very few lisp branches that I can't find Chesterton's fences[1] in. I don't think this is because there's anything wrong with lisp, but rather that it's very very easy to write a any lisp dialect, which means you get a lot more bad ones. You need to do a lot more work to write a bad
1: https://en.wikipedia.org/wiki/G._K._Chesterton#Chesterton's_...