Why I chose TypeScript over JavaScript is because I believe that static/strong typing is great for developing a product for scale in the long run. It gives you predictability and confidence on building your application.
I had one problem with JavaScript dealing with data types in a production environment that unit tests didn't even catch. Users are seeing undefined words instead of information the user is fetching from a specific API to deliver the user's needs.
We also use TS exclusively in our code. We are application developers and not a computer language scientist. We need all the help from IDEs like IntelliJ and Visual Studio to help us code accurately, and in the case of TS and tslint combo, they can keep a lot of troubles away. While we certainly do not recommend it, the type "any" can be used in a pinch. We enforce Zero Warning in code we commit.