For the time being is there anything stopping people from using two virtual machines with direct PCIe passthrough of 8 GPUs each? Will have a bit more overhead than it could but a lot less than the overhead of 2 extra systems.
I noticed yesterday that there is a cryptocurrency named "Ripple". That brought a belly laugh. Some years ago here used to be a brand of vino in the States named "Ripple". It was quite popular with the Winos. It didn't taste like much but it was good for getting drunk.