[nawitus]

I agree.

One benefit I've seen a lot is typing external services. A lot of code (both the frontend and the backend in say Node.js) tends to deal with calling external APIs, which would be dynamic in JavaScript and end up being quite loosely documented in the code.

With TypeScript, however, you can type in the JSON responses, which makes reading any code dealing with external services so much quicker. And these days with literal types you can even document that a particular property is either "magic_string_1" or "magic_string_2".