There is so much complexity in interactions of systems that is easy to miss.
Saying that one can understand a modern CPU by understanding how a transistor works is kinda akin to saying you can understand the operation of a country by understanding a human from it. It's a necessary step, probably, but definitely not sufficient.
It also reminds me of a pet peeve in software development where it's tempting to think you understand the system from the unit tests of each component, while all the interesting stuff happens when different components interact with each other in novel ways.
Saying that one can understand a modern CPU by understanding how a transistor works is kinda akin to saying you can understand the operation of a country by understanding a human from it. It's a necessary step, probably, but definitely not sufficient.
It also reminds me of a pet peeve in software development where it's tempting to think you understand the system from the unit tests of each component, while all the interesting stuff happens when different components interact with each other in novel ways.