It provides a runtime, that sandboxes your application and requires you to give explicit permissions for file system operations and network requests.

This limits the attack surface, when it comes to installing malicious dependencies, that npm happily installs for you.

So yes, I was wrong and my previous comment a hyperbole. A big problem is npm, and not JavaScript.

My point about the staggering amount of dependencies still holds though.

Of course, this only works so long as the sandbox is secure.

There have been attempts to do this kind of sandboxing before. Java and .NET both used to have it. Both dropped it because it turns out that properly sandboxing stuff is hard.