Interesting considering the article, it was a defining part of Commodore hardware design that they compensated for slow CPU's by using co-processors all over the place, including putting a 6502 compatible CPU in the keyboard controller for the A500 and A2000...
(But you'd also find this spilling over into 3rd party hardware: My HD controller for my Amiga 2000 back in the day had a Z80 on it.
That machine was totally schizophrenic: In addition to the 6502 core on the keyboard, the M68k main CPU and the Z80 on the HD controller it also had an x86 on a bridge board - the A2000 had both Amiga-style Zorro slots and ISA slots, including one slot where both connectors were in line where you could slot in a "bridge board" with an 8086 that effectively gave you a PC inside your Amiga, with the display available in a window on the Amiga desktop).
(But you'd also find this spilling over into 3rd party hardware: My HD controller for my Amiga 2000 back in the day had a Z80 on it.
That machine was totally schizophrenic: In addition to the 6502 core on the keyboard, the M68k main CPU and the Z80 on the HD controller it also had an x86 on a bridge board - the A2000 had both Amiga-style Zorro slots and ISA slots, including one slot where both connectors were in line where you could slot in a "bridge board" with an 8086 that effectively gave you a PC inside your Amiga, with the display available in a window on the Amiga desktop).