Well, according to [1], NVIDIA lists NVLink 3.0 as being 50 Gb/s per lane per direction, and lists the total maximum bandwidth of NVSwitch for Ampere (using NVLink 3.0) as 900 GB/s each direction, so it doesn't seem completely out of reach.
Fascinatingly, NVIDIA's own docs [1] claim GPU<->GPU bandwidth on that device of 600 GB/s (though they claim total aggregate bandwidth of 9.6 TB/s). Which would be what, 96 and 1536 lanes, respectively? That's quite the pinout.
[1] - https://en.wikipedia.org/wiki/NVLink