I mean the goal is more performance, especially if you can get more performance out of the same hardware. Faster setup times, faster connections, more connections, maybe faster teardown. Lower contention on saturated links. Inside of the datacenter is a controlled environment where something like that could work. Replacing TCP over the Internet at large is going to be an uphill battle. Still, if we're replacing the whole thing, then simpler code on the client and server end would be nice.