It should be the job of the operating system to expose a coherent and flexible set of tools, features, and UI paradigms that people can use across many differen

It should be the job of the operating system to expose a coherent and flexible set of tools, features, and UI paradigms that people can use across many different use-cases (nowadays called "apps"). Copy and Paste, although poor operators in retrospect, is such an example. Undo is an other, much better one. I firmly believe that we could reduce or eliminate most application-specific commands by increasing the standard set provided by the OS. Some kind of semantic primes that could be composed into anything. A new UI language if you will.