I dunno. AVR-8 is basically the last 8 bit CPU so it is much better than the CPUs we remember from the 1980s like the Z80, 6502, 6809, in most respects except RAM size. 32 registers is a lot! It also takes advantage of the Harvard architecture and has none of this pipelining and cache BS, most instructions take a cycle so if it runs at 20MHz it is basically running at 20 MIPS. Assembly language is beautiful and thinking about writing C for it makes me want to cry.

The one issue is that it has no upgrade path to anything more powerful so if you want something better it is going to be ARM or ESP32 so you might just keep writing portable C.