I'm going to have to disagree with that notion of a C# developer being able to pick up javascript faster than vice versa. A solid developer would be able to pick up both with relatively similar speed. C# is a bigger language, but Javascript is very unconventional and the current JS environment is very unstable. The basics of Javascript are simple, but there are a ton of JS quirks that take a time to learn and when you get into all of the functional and asynchronous programming, things start ramping up in complexity. Couple that with not knowing ahead of times which features you can use do to different browsers not supporting this or that feature can make things headache inducing.
What I've seen is that a lot of Java developers and the such actually hate working with JS and on the front-end because it is so drastically different from what they are accustomed to and having to deal with several browsers with that may or may not support this or that language feature and then having to deal with several different screen sizes.
From my personal experience, I've found the basics of Javascript a lot easier to learn since you don't have to deal with types and all of these other keywords, but after that, I find C# and Java easier to understand past the basics since things are more clearly defined and knowing ahead of time what types are accepted by a function makes it a lot easier to understand what code is doing.
Thank God for things like ES6 and Typescript and transpilers, because they eliminate a ton of annoyance that you have to deal with in the JS language.
CSS is even something that I find difficult to work with. Knowing the rules of CSS and being able to slam together a few rules is easy, but making a full-fledged site with it is fairly headache inducing if you aren't using a framework like bootstrap, especially if you're going for a responsive website.
I guess it depends on what area you live in, but 65k seems low for a full-stack developer with 2 years of experience. For example, here are a couple of listings I've come across:
Python Developers needed - Austin - $80-120k job - Roc Search - Austin, TX
Ruby on Rails Developer - Downtown Austin - $75-85k job - Roc Search - Austin, TX