I always love to see people investigating older consoles. I did some Fame Boy Advance programming in the past, which was (I believe) one of the last machines that was programmed entirely "on the metal", you just put values in particular memory locations and sprites moved and spun about :)
This was great. As usual I marvel at the ingenuity that went into game development back then (probably still does).
It really was a different universe when complex games were developed entirely in assembly, with simple tools, for very limited platforms.
There are plenty of challenges in modern game development, but many of them can be avoided if you're not trying to push the hardware to its absolute limit.