Regardless, I don't see much of a difference between TS -> JS and haskell->JS and scala -> JS. It's all from one language to another. the fact that TS is still considered a form of javascript is kind of irrelevant other than for semantics
Are they different? If language X can be expressed in its entirety as language Y then we can speak about X and Y interchangeably -- that's literally the point: full interop between client and server.
Anyway, there's a world of difference between TS and GHCJS, Scala.js, Clojurescript, Js_of_ocaml, etc. One speaks javascript, the others speak both.
As for reliability, in so far as TS is typed it will provide the compile time guarantees that its type system provides; not surprisingly the same goes for Scala.js, GHCJS, etc.
So, the decision point probably hinges more on aforementioned overhead, size of community, and tooling than language/type system features/power. If it were otherwise we'd have seen a huge uptick by now wrt adoption rates for the compile-to-js languages. Maybe that will change in future but for now the big players drive the javascript bus...