Worth noting that at the same time, "they" weren't good enough at pushing new things that the same time. For example, all new compression methods work only over HTTPS (actually, this alone can be a reason to switch to HTTPS) - because they were incompatible with some HTTP proxies: https://bugs.chromium.org/p/chromium/issues/detail?id=14801

<rant> I'm actually looking forward for them to drop HTTP digest auth, because it's the only auth scheme which doesn't rely on sending shared secret over the wire with each request </rant>