It'll be interesting to see if they leverage any new hardware features I've heard of in the past 3 years. One is AMD got the feature that allows PCIe to be DMA'd directly to L2|L3 working. Another is something about PCIe devices being able to talk "directly" to each other. Pretty sure it's actually mediated by the PCIe controller though.

Alas, this is beyond any level I expect to ever see 1st hand, so I didn't retain more detail than I've given.

Notably, ConnectX-8 already has 200G PAM4 for 800G as a single port - and uses it for Infiniband.

Looks like it is so because it pre-dates 800G Ethernet ratification...