So much about how processor design has evolved isn't about stuff we've learned, it's about how moore's law has allowed us to have more gates for the same cost, and "what is the best use of all these new gates". 8051s are still pretty competitive in their gate count niche.
It's sort of like how MIPS never really got a lot of traction outside of 5ish stage, in order, optional FPU designs. That's ultimately the gate count niche where they're still competitive.
It's sort of like how MIPS never really got a lot of traction outside of 5ish stage, in order, optional FPU designs. That's ultimately the gate count niche where they're still competitive.