[MuppetMaster42]

It's really not though. If you look at the official yearly releases, you'll find that there have only been a few major changes since ES5 (aka ES2009): Async/await, modules (import/export), arrow functions and destructuring.

None of those are mandatory. They're mostly just syntactic sugar on top of existing features.

Every other change has just been things like new util methods on primitives like the string trim functions.

The build tools are separate, don't conflate them with the language. That being said, for ~4 years, most people's build chain hasn't changed; webpack with a babel plugin.

The problem is that JavaScript wasn't considered a stable and useful language until it really started to hit its stride in about 2009. So all of the changes that have happened are because the community is still figuring out the best way to do builds whilst things in the language are still changing.