It's easier to create correct HTTP/2 implementation than HTTP 0.9/1.0/1.1
I had enough weekends wrecked by someone thinking they can implement HTTP themselves, only to find out that no, they couldn't, and that was for cases that didn't even hit corners. A netcat "HTTP server" demo is cute, but the power of the computer is that we make tools to make tools that can cover things like HTTP/2 reasonably fast - and much more correct.