This. There are already complaints about the cost of USB 3.2 hardware, because measurably charging a hunk of metal gets a lot harder at high frequencies. They h

This. There are already complaints about the cost of USB 3.2 hardware, because measurably charging a hunk of metal gets a lot harder at high frequencies. They had to get more precise and then start borrowing tricks from SATA and PCIe. A 6502 could go up to 3 MHz, but I think the C=64 ran its 6510 near 1 MHz because a clock divider was reserving half the bus cycles for the video chip (no dual-ported VRAM). With dies too small for cache, it didn't make sense to make anything faster than fetching instructions from RAM or ROM. Even the Cray-1 was only able to run at 80 MHz (12.5 ns/cycle) because they paid for four banks of 50 ns RAM. And at those speeds, you could just glue straight wires together into a ribbon cable and call it a day.