It means you can get started right away. If you want to be more serious, sure, write stuff in C or whatever, it works fine, after all this is just a Linux machine (with a simple webserver running cloud9 on port 3000). Or just ssh into the bone and edit your .js files in vim (it probably makes you feel a little bit more hardcore but yeah, it's still js).

No need for the negativity, can't blame those guys for wanting to get a larger userbase by making things easy. In the end the larger volume/bigger community is beneficial to everyone.