Two more guys understood the situation
"The developer made it proprietary because he got pissed that some people had some ideas of their own and spun them off in a fork called KolibriOS. Wanting to keep the project wholly "his baby" and not have to share with other people, he was a jerk and closed the source."
"Anyway, back on topic. I must say MenuetOS doesn't impress me much anymore. It's awesome that it's in assembly, and it's real neat, but it has it's flaws. For one thing, being written in assembly, it's not as fast as it should be (or at least, it doesn't feel as fast as even Windows, certainly doesn't feel as fast as *nix). Also, it's not a very good development environment, IMHO.
That being said, MenuetOS is an amazing hobby OS... probably my favorite. Very unique. But since MenuetOS 64-bit was released, it seems that the userbase has been shrinking (or is it just me?)"