> you can downgrade 10gig-t to 10m/s that has no bearing on its performance, unless you terminate it badly. Its just a preamble, then for the life of the connection, an utter irrelevance.

You misinterpreted "downgrade" here (though maybe I chose a bad word for this.) I didn't mean that the proxy itself can force both sides to speak HTTP/1.1 to it. I meant that a proxy can be speaking HTTP/{2,3} to one side, while speaking HTTP/1.1 to the other, by translating ("downgrading") HTTP/{2,3} messages into their equivalent HTTP/1.1 messages. This is the reason that HTTP/{2,3} are HTTP in a real sense: the messages that flow over them still interoperate with the rest of the HTTP ecosystem, through bilingual gateways. The messages are a different bijective encoding of the same HTTP application-layer message-flow semantics.

(Nginx, by default, is such a gateway: it speaks HTTP/2 to clients if they offer, but speaks HTTP/1.1 to upstream backends even if they know how to speak HTTP/2. This is because HTTP/2 is useful to carry flows over the Internet, but has few advantages within a low-contention low-packet-loss LAN.)

This also has other implications, like the fact that browsers and caching proxies don't need to change the way they store cached HTTP resources, just because the resources come in over HTTP/{2,3}. They can just transcribe the messages to disk as if they had been the equivalent HTTP/1.1 messages.

> Lets get one thing clear, HTTP is, has never been and almost never will be efficient. The entire HTML/JS/HTTP web is never going to be efficient. If the web was a meritocracy based on protocols, HTTP would have died a death at CERN.

The point is to take a stupid thing that people will keep on doing no matter what (for better or for worse), and help them to do it as fast (or as un-slow) as possible, without trying to make it non-stupid in the process (because that won't be the same thing any more, and so people won't use your smart thing, but will continue doing the stupid thing.)

You know Formula 1 racing? In F1, there are rules against doing most things that could make cars go fast. The point of the competition is to make the cars go fast anyway, without breaking those rules. If you make the car go as fast as it can, it's not an F1 car any more. To win, you've gotta make the fastest F1 car, not the fastest car.

That's HTTP/{2,3}: the cars are the flows, and the rules are HTTP's must-be-all-things-to-all-people semantics and manifold optimized-for usecases. The goal of adding HTTP extensions/versions/etc. is to make your server (or client) talk to clients (or servers) as efficiently as possible, without breaking any random peer from 1996 speaking to you through a bilingual gateway. If you did break those peers, you might have the fastest protocol, but you wouldn't have the fastest HTTP protocol.

> They'd terminate the connection as close to the client as possible and palm it off to the local FAANG pop and make it someone else's problem. That and adding pop's for porn hub and torrent filters will knock out >70% of your precovid interconnect traffic.

That's an infinite regress, as the people who you're handing the problem off to are also Internet backbone engineers. If your company owns 30% of the Internet's traffic, your leaf-node AS is part of the backbone, and that AS's problems are the Internet backbone's problems. Just like the major universities were part of the backbone until ~1990.

Though, keep in mind, this isn't about fancy application-layer-aware routing or anything. HTTP/{2,3} have bandwidth savings, and that savings is passed directly onto the Internet backbone those messages travel along, in the form of more headroom for other stuff. It's not about needing to pay peering fees; it's about e.g. packing more clients per head-end fibre switch for an ISP. Or, to put that another way: it's about making more money out of the same aggregate delivered traffic volume, by having that volume represent more customers.

That's why the carriers are interested in participating in the development of these protocols: not because they need to do anything with them in their operational lifetime, but because the effects of the choices made by the HTTPWG have the potential to ripple out and create huge (e.g. 10+%) reductions in their aggregate traffic load (which they can then re-oversell); and they want to do what they can to argue for whatever designs best make this happen.