"I can code in X so I should be able to jump in to any other language and get to speed instantly." is obviously wrong.
You can nest functions nicely and work with closures when it makes sense, if you like that sort of thing.
The async programming model is also really nice to work with.
You also don't need to create classes for every noun, verb, and adjective in your system either - when all you need is a function, you just write a function, not some weird object to hold it.
You also don't have to write a f after all of your decimal values to tell the silly compiler that you mean for 0.25 to be a float. (this one truly does not matter, but there are a lot of little things like this that add up)
I know you can do a lot of that in C#, but its just so effortless in javascript. You just need to be more disciplined about how you code it