PCIe 4.0 x4 lane provides enough bandwidth. Ish... we've already capped out with 8GBps SSD actually. PCIe 4.0 x4 lane is now the limiting factor.

PCIe 6.0 1x lane would provide the same bandwidth, meaning you run 1/4th as many wires and still get the same speed.

Alternatively, PCIe 6.0 4x lane will be 4x faster than 4.0, meaning our SSDs can speed up once more.