The author is clearly claiming that feature is unique to Swift: "Why did no one think of this before?"

The author is short-sighted. He doesn't know any descent modern OO language, but tries to review Swift. Except ARC and syntax differences, it is more like a subset of F# or Scala

I don't know F#, but Scala certainly addresses all three of his issues:

1) override (also in C#, IIRC)

2) The Option type (which, being a monad, also has compositional ability null/nil doesn't have)

3) Case classes

That's what I said. Swift is a subset of F#/Scala.