This reminds me of Harvey Cragon's intro to computer architecture textbook...

When it introduces Harvard vs. Von Neumann architectures, it doesn't invent some dumb RISC computer to illustrate the difference... No... it makes you learn the actual von Neumann machine! Also Conrad Zuse Z machine.

Cragon's argument is that students will not learn the concept of engineering trade-offs, if presented with a clean "textbook" architecture.

I hated MIX for various reasons, it's sort of in-between simple and kludgy.

[0] Cragon was professor at University of Texas Austin ca 1980. Also the architect of TI's ASC in the 1960s.