I am one of those JS guys who like to put JS/Node.js everywhere, but I do not get the problem Redbird is trying to solve: the Express.js doc is quite clear that for serious things, you should use a dedicated http server. [1]
If you just want reverse-proxying, you can choose between the simplicity of Caddy or the power of Nginx (or Apache). Why would I want to run a JS app (that I know will be less performant) to do that?
[1] https://expressjs.com/en/advanced/best-practice-performance.html