It also makes hardware offloads like TSO and LRO impossible, and increases cost-per-byte served by a factor of 4 or more. So if you have infinite CPU to throw at QUIC and/or low bandwidth or connection targets, its great. If you are concerned at all about server-side efficiency, its terrible.
FWIW, I work on the Netflix CDN, and specialize in server-side efficiency; we have had 100G flash CDN nodes for years serving at 90G+ in production. None of that would be possible with QUIC as it stands. I suspect our max B/W on these machines would drop from ~95Gb/s to 20Gb/s or less if we were to switch to QUIC.
Don't blame QUIC. Blame ISPs and middlebox makers for abusing their (literal network-wise) position and breaking the end-to-end principle. History has shown that we just have to encrypt everything and quite literally cut out the middleman/box.
FWIW, I work on the Netflix CDN, and specialize in server-side efficiency; we have had 100G flash CDN nodes for years serving at 90G+ in production. None of that would be possible with QUIC as it stands. I suspect our max B/W on these machines would drop from ~95Gb/s to 20Gb/s or less if we were to switch to QUIC.