Difficult to summarize, but the short answer is: immutability, reproducibility, and reversibility (i.e. you can revert/de-revert almost any change instantly).

Difficult to summarize, but the short answer is: immutability, reproducibility, and reversibility (i.e. you can revert/de-revert almost any change instantly). It's on another level, as compared to Ubuntu, but it's also much more intrinsically demanding. And lately it has unfortunately become a culture war battleground.