In consoles the CPUs is (or was) usually there to control games logic, communication with internal chipset and players input, the rest was entirely handled by specialized chipsets for speed considerations (and production cost), the neo geo had a graphic chip able to handle 380 sprites of 16x512 pixels & 3 playfields.
On computers like the Amiga (and even more on the Atari ST) the role of the CPU is more preponderant as the architectures of the machines are more complex by nature (since there's much more possibilities, more peripherals to control, etc.) so it was also used to clear screen or to calculate positions of bobs on screens and so on, all eating precious cpu cycles.
Also most consoles (and older computers like the MSX) had tiles based graphic chips meaning that once the tiles were loaded inside the graphic memory of the chip any could be displayed at will on the screen with usually something like 1 CPU instruction & the specialized hardware did the rest, it was fast for games as they were created back then but not really good to display pictures, complete set of OS windows, applications, etc.
So basically most of these consoles are fundamentally different from the Amiga in their approach because their primary purpose was different.