Node.js has only limited uses cases and should not be applied everywhere. It is good as a part of your application as a stand-alone service but it, probably, should not be used for serious financial/banking systems.
It is a new product comparing to enterprise solutions using Java/PHP which worked for many years.
JavaScript is a browser language, it is cool, yes, but it should not be used everywhere and yes, JavaScript is one of the most WTF languages in the world and WTF is not allowed in serious back-end.
Node.js doesn't really solves any back-end problem. Non-blocking I/O and async is available in other platforms or additional packages on those platforms.
That's also why I am still using PHP as my primary back-end language. PHP7 and Laravel5 makes web development great and fun again.
1 further - finance / banking / medical generally prefer transactional databases. While NodeJS can work with SQL connections, NodeJS apps generally prefer document stores and a document store in these markets I'm willing to bet is rare to none.