The fact that it was Notch gave it visibility, but I think the following is more than just design or cult-of-personality.
Simplicity is extremely important. A lot of emulators appeared the same day that the spec was released. That not only needed people who wanted to implement the CPU, but also a spec that could be implemented in under a day.
There's a bit of Benevolent Dictator effect here as well. It's not that the system is the absolute best, but it's something that people can target for interoperability. Someone can write a compiler and someone else can write the emulator.
Simplicity is extremely important. A lot of emulators appeared the same day that the spec was released. That not only needed people who wanted to implement the CPU, but also a spec that could be implemented in under a day.
There's a bit of Benevolent Dictator effect here as well. It's not that the system is the absolute best, but it's something that people can target for interoperability. Someone can write a compiler and someone else can write the emulator.