Many comments about static typing in here. I agree that it is a great and helpful feature, and it's also not the only feature. For many other reasons, my languages of choice are mostly PHP, Perl, and JavaScript. And I have experienced the types of bugs that static typing (and also immutability) can help with. What I have found extremely helpful is to write as if variables are immutable, not allowing myself to change…
You can configure TypeScript to give you the output for older versions of ECMAScript. No need to limit yourself and you get many benefits (not just strict typing but also some constructs like interfaces and enums to easily scale your codebase).