I was thinking lately about how much memory you could handle on a 6502. The BBC Micro had a 16KB block of RAM paged between up to 16 ROMs/RAM but if you could have 256 banks you could do 4MB. The only problem is that that would require a very large PCB.

It could be useful for some sort of minicomputer for business applications.

I believe the actual silicon of a 6502 is much smaller than the DIP package, so even if we couldn't shrink the silicon itself much more, you could just take up more space inside the package, and use a package that has more pins in it, like current CPU designs. You would probably hit a bottleneck at some point since I believe the speed of light is a problem for processing speed at some point, but then I'd expect we'd just go into massively parallel systems, with multiple cores acting somewhat individually

Laptops would be a lot less common. If computers were stuck in this era for that long, fewer people would be interested. Prices would be high.