In a similar case TypeScript even knows the signature of the event handler for addEventListener, and what type of Element document.createElement('div') returns. Someone even built typings for querySelector that parse the selector and returns the correct element type.
In general, however, I still think APIs written in TypeScript first are a lot cleaner type-wise than typings retrofitted onto a JS API. And having TypeScript as an afterthought these days doesn't seem like a good path to go anymore.
