answer:The terms of your question aren’t very solid. One could say that “the norm” is subjective, and that some people already use it every day (I do, for example, as do many others). It’s already “a norm”, and I’m not sure how much more meaningfully that can be answered. (Semi-relevantly, MacOS X’s core is developed from Unix and NeXTSTEP, so it shares some similarities but isn’t Linux.)