node.js doesn't run in the browser. It's typically a server side application. And, yes, I think most would agree that node.js might be one of the few valid use cases for this.
Except this library doesn't have proper memory protection, and node.js has system access so it could just use GnuPG and be a lot more secure (and almost certainly faster, too).
Thank you. So it makes some sense to me, developing this kind of library. Even if they have a marginal usability spectrum.