The 6502 didn't need cache because its clock speed was slower than the DRAM connected to it. That made memory accesses very inexpensive.
The Apple II took advantage of the speed difference between CPU and DRAM and designed the video hardware to read from memory every other memory cycle, interleaved with CPU memory access.
> The Apple II took advantage of the speed difference between CPU and DRAM and designed the video hardware to read from memory every other memory cycle, interleaved with CPU memory access.
Same for the C64. Sometimes it was necessary to read slightly more than that for video display though, so the VIC (video chip) had to pause the CPU for a bit sometimes, resulting in so called "badlines".
Both were faster. DRAM was a little cheaper, but required more circuitry to handle refresh on most CPUs making it a wash cost-wise on some designs. Typical woz engineering got the cost of the refresh circuitry down to where DRAM made sense economically on the Apple ][.
Interestingly Z80s had DRAM refresh circuitry builtin which which was one reason for their prevalence.
And for the Z80: also that it only needed GND and 5V. The 8080 also needed 12V. And the Z80 only needed a single clock phase -- the 8080 needed two. The 6502 also only needed 5V and a single clock input (the 6800 needed two clock phases). The 6502 and Z80 were simply a lot easier to work with than most of the competition.
The Apple II took advantage of the speed difference between CPU and DRAM and designed the video hardware to read from memory every other memory cycle, interleaved with CPU memory access.