HTTP/2 doesn’t replace the need for UDP at all, not in the slightest. For latency-sensitive applications, it provides no advantages over HTTP that I can tell.
The problem is with TCP, and the problem with TCP is that it prioritizes in-order delivery, and missed packets cause head of line blocking. HTTP/2 is designed to solve head of line blocking, but since it’s built on top of TCP, it can’t solve the issue in this case.
The problem is with TCP, and the problem with TCP is that it prioritizes in-order delivery, and missed packets cause head of line blocking. HTTP/2 is designed to solve head of line blocking, but since it’s built on top of TCP, it can’t solve the issue in this case.