> in the first test, h1 compound is just as fast as h2

That's because HTTP/2 auto-compounds multiple requests to send in the same connection, thus there is no surprise there.

The main advantage of HTTP/2 is that it ensures that we can get the same benefit of compound data transfers in a completely transparent manner, without bothering to rearchitect how clients and servers operate.

> Considering all the additional complexity that HTTP/2 introduces, that doesn't seem like any improvement.

This assertion completely misses the whole point of HTTP/2, and why it's a huge improvement over HTTP/1.1.