Because that’s what people want. That’s how you can get a really good developer experience similar to golang or other languages. Just install one tool to build,

Because that’s what people want. That’s how you can get a really good developer experience similar to golang or other languages. Just install one tool to build, lint, format, run tests, run your local project. No time spent trying to setup a bundler when what you want is to build a new project. Regarding runtime libraries, it’s similar to the battery-included approach of go or python, you get what you need to get started out of the box and only reach for dependencies when you want to go further. Testing library, an http server, a websocket server that’s perfectly reasonable to have as core library of a runtime developed to run web servers.