I would align with this philosophy as it relates to learning. Complexity is a likely a necessity of technological advancement, but a hinderance to 'from-scratch' learning. Abstractions hide many details that may not be needed to operate, but are needed to understand.

The entire retro-computing field is interesting and a bit surprising in it's strength. I would not have guessed that in 2023 an IMSAI 8080 would be selling for ~$3-5k, and that there would be such an active community of people doing things in CP/M. Nor would I guess that I would be working on either of these!

One of the most enjoyable personal projects that I have worked on was the creation and implementation of a CPU, starting with the concept ISA and building the microarchitecture, making lots of cool mistakes that require rework, and eventually having a booting CPU running code in an assembly language of my own. While the performance of a CPU like this is closer to the computational power of my coffee maker, it is still an excellent experience.

I ordered my copy of your book and am looking forward to reading it!