An undergrad computer architecture course would typically gloss over the history of CPUs and focus either on MIPS or x86 (or both). For example, I did two courses on x86, starting from 8086 (and 8088), through Pentium, and some bits of Itanium.

You're right that starting with a simple architecture makes things much easier. 8086 for example operated in 16-bit real mode (segmented memory), and so the memory layout was trivial compared to 32-bit protected mode in x86.

I haven't taken any graduate architecture courses yet, but my assumption that they would go into more detail on the development of CPUs through history.