That analogy is not correct. He isn't running existing binaries in an emulator. He cross-compiled code to a new platform, using a new compiler and toolchain, and made sure everything worked in the entirely new environment. And as he mentions in a comment, he found, reported and fixed some bugs in the compiler and toolchain while doing so.

And remember that the web platform is different than a normal desktop environment. You can't just compile code and expect it to run perfectly (it often does for small apps, but larger ones generally no), for example, the main loop has special requirements, threading as well, etc. It's the same as porting a Windows game to the iPhone, for example - there are different APIs, different expectations of how the OS works and what it allows you to do, etc. Such ports take work.

So your dismissal of his work is very unfair.