Agreed, and TypeScript's ease of writing code correctly and quickly is what finally got me away from Ruby and to Node almost all of the time. ES6 was legitimately nice and could have been good enough for about the 50%-75% case, but the ease of building expressive TypeScript typings that let the compiler tell me what I was screwing up without having to write insipid typechecking tests or repeatedly running scratch code sold me. And when I have to do something that TypeScript can't prove, it's very easy to just bail out, do my filthy misdeeds, and patch back into the type system after.

For awhile, React/Redux was really kind of gross with TypeScript, but even that's mostly hammered out. (React's new context API did a lot to reduce my use of Redux in general, and works pretty comfortably with TypeScript too.)