The possibilities are greatly extended when you have separate memories for sprites and playfields.
80s computers were limited by sharing memory, and a limited amount at that, for reasons of cost and the fact that pins on chips actually cost a lot once you reached a certain number.
There's no reason a 6502C can't drive an amazing graphics subsystem on its own, when the subsystem has no memory or pin limitations to deal with.
However, in case I sound like a sourpuss, this is still a brilliant achievement in so few discrete 74 series chips.
