How can they mention Ceylon, Eiffel, Kotlin, and PPL (the latter two I've never heard of, and I've heard of a lot of programming languages) and not mention Hask

How can they mention Ceylon, Eiffel, Kotlin, and PPL (the latter two I've never heard of, and I've heard of a lot of programming languages) and not mention Haskell, ML, OCaml, etc? It's been mentioned in other comments, but essentially all of the supposed downsides of the Optional solution are implementation weaknesses in either the type system (allowing null anywhere, regardless of type) or runtime (there being overhead of Options) - which seems like a pretty weak argument for loving null.