This standard is a change to IP, which TCP and UDP (and transports implemented on top of UDP) are both implemented on. So it applies to all of them. Each transport has to implement its own way of using it.

I think the key point is the bottleneck link is a shared resource. Many TCP flows traversing the link will drive it to a relatively high queue occupancy which causes higher delay for all traffic regardless of protocol.

Only skimmed the proposal but looks like it isolates traffic using the new protocol by giving it a dedicated buffer, and the explicit congestion notification protocol would then keep the size of this queue much smaller at steady state when the link is saturated.

You ever get that robotic latency thing? That’s because of udp and the stream allowing dropped packets at all. It’s a horrible experience.

You can use udp and still do much better through things like adapting reed solomon or simple XOR error correction to packet loss statistics.