Much simpler. For IPv6, every hop in the path between the client and the server has to understand the new protocol. For HTTP/2 and HTTP/3, only the endpoints (t

Much simpler. For IPv6, every hop in the path between the client and the server has to understand the new protocol. For HTTP/2 and HTTP/3, only the endpoints (the client and the server) have to understand the new protocol. And since they run on top of TCP (HTTP/2) or UDP (HTTP/3), not even the operating system on either endpoint has to understand the new protocol; only the client application (the browser) and the server application (the HTTP server daemon).