They definitively pushed HTTP2 to help their clients move away from HTTP. My guess is they cannot make stubby public without disclosing too much valuable advant

They definitively pushed HTTP2 to help their clients move away from HTTP. My guess is they cannot make stubby public without disclosing too much valuable advantage and probably also knowing that this can only effectively run on their own DC at that point. At least, gRPC is easy to unwrap from HTTP (which is likely the very first step of processing on their side). Regarding protobuf, I'm not a big fan but at least that's not JSON (another awful tech that the industry is taking for granted). Also: TLS is slow, and last time I asked for the best practice to do client auth on HTTPS the general consensus seamed to be "don't do it".