Lately, TypeScript has become more scalable across existing npm libraries and also introduced new advanced types. It looks like Microsoft guys learned a lot from C# and F# type system and feedback from their users
https://www.typescriptlang.org/docs/handbook/advanced-types....
Typescript is Javascript with a relatively advanced type system (mapped types, type guards, etc) on top, but is still very much constrained by Javascript fundamentals and syntax.
The type system evolution was primarily driven by the need to create valid typings for the existing JS ecosystem, and this noticeably shapes the capabilities.
This is the right choice for the language, but I can't see how it resembles the ML family much.
Typescript in the last couple of years introduced a nice way to compose types and ways to get rid of many other common JS gotchas. They have type definitions for almost all the usable npm libraries, which helps you jump-start the development.
https://github.com/purescript/package-sets/releases/tag/psc-...
ClojureScript == Lisp
PureScript == Haskell
Reason == ML
TypeScript == C#
But now Typescript 3.5 is also influenced by F# which is close to ML.
Just look at those advance types and their allowed composition which Typescript supports in its latest release and you will understand.
If you want ML, why not OCaml with js_of_ocaml or BuckleScript?