Agree. Most computers that are a joy to learn have a handful of controllers that operate in parallel. That is, multiple cores

The Apple II had a really cool disk drive because of how it did what it did with so little hardware. By relying on the single CPU for everything it was elegant, advanced, interesting... but perhaps not so easy to program.

https://www.bigmessowires.com/2021/11/12/the-amazing-disk-ii...