I'd be more optimistic about official type annotations for JavaScript if said typing was less like the particularly unique syntax of TypeScript and more like that which already exists in C-family languages. For instance, in Typescript, we can do this:

---

const user: User = {

  ...

};

---

Why couldn't this be more like C rather than this weird conflation with the existing colon token?

---

const User user = {

  ...

};

---

That might seem not as pleasing to those familiar with Typescript, but it's much closer to other existing syntaxes (meaning less of a learning curve coming from Java or C).

Same with function definitions:

---

function foo (bar: string, baz: boolean): Qux {

  ...

}

---

Versus:

---

Qux function foo (string bar, bool baz) {

  ...

}

---

I find the latter much more familiar than Typescript and less confusing. It's also slightly less verbose.