I do occasionally wonder how different things would be if JavaScript had come with a very robust standard library from early on.

I also wonder about it recently. Also in regards to Rust which is hailed as the great savior but has the same, minimal, approach to standard library and needs loads of dependencies.

The crazy thing is that today the JavaScript standard library is very robust, and yet the culture of pulling in a ton of dependencies persists. It's so much easier to develop code against a stable and secure platform, yet it seems the choice is often to pull in hundreds of bits of code maintained by many different parties (instead of doing a little more in-house).