I had a fevered dream the other night where it turned out that the bulk of AWS’s electricity consumption was just marshaling and unmarshalling JSON, for no benefit.
Anyway, along this journey I discovered that it's surprisingly difficult to get a HTTPS JSON RPC call below 3ms latency even on localhost! It's mindboggling how inefficient it actually is to encode every call through a bunch of layers, stuff it into a network stream, undo that on the other end, and then repeat on the way back.
Meanwhile, if you tick the right checkboxes on the infrastructure configuration, then a binary protocol between two Azure VMs can easily achieve a latency as low as 50 microseconds.