I think this was more to point out that for those who like the functional aspects of Scala's type system with respect to Java's, but don't like being hamstrung

I think this was more to point out that for those who like the functional aspects of Scala's type system with respect to Java's, but don't like being hamstrung by the need for Java compatibility, Rust has the goods. I didn't read it as espousing static types for FP a priori.