I'm not expecting to get those jobs without any experience. I'm saying that some of those listings were low for full stack development, especially for 2 years of experience. If you've got 2 years of experience and a solid github/apps deployed on heroku, with your inbox will be flooded with offers if you live in one of the tech hubs. Having 2 years of experience at a solid company and getting offered $60,000 is a lowball offer. I don't believe $55-60,000 is excessive for entry level, especially if you have a solid portfolio.
All of the things about avoiding deep inheritance chains, dependency injection, etc apply to modern Javascript development. Increasingly more complex apps are being built with it, rivaling many desktop apps. You have your 3d games (webGL), emulators, paint programs, etc. JS development today isn't like JS of 5 or 10 years ago. It has become significantly more complex. One of the main avenues where Node.js excels is for realtime apps.
Paypal actually moved from Java on the backend to NodeJS:
Node.js at PayPal | PayPal Engineering Blog
Microsoft made JS a first class language in VS mainly because they see the huge potential in it. One of the main reasons for the prevalence of JS is that you can 'write once and deploy everywhere' due to every OS having a browser. You can even build native mobile apps using things like PhoneGap, Cordova or React Native.
Here's command and conquer created in Javascript:
Command and Conquer - HTML5
3d games in Javascript
Babylon.js demos & documentation
C# is the focus of unity because most people find C# a superior language to work with, which I can't argue against. With that said, RPGMaker switched from ruby to JS and you can even embed your games right into the browser. JS isn't the most elegant language, but it isn't the simple script kiddy language that it had it's reputation for. As of now, it's the only way to access the front-end and apps being built in JS are getting as complex as apps in any other language. It may not be the most optimal language for huge apps, but people are making them, and it's also one of the reasons for Typescript, which is pretty much JS with types and a few other features.
RPGMaker game in the browser
Areath: The Shadow's Edge