I was going for brevity but the downvotes tell me I said too little. CoffeeScript is a tool by and for experts. I don't know where people got the idea it is there to help newcomers. It's clearly an opinionated abstraction that is designed around removing the things that are grating to deal with as professional JS programmers on large code bases. The benefits on a line by line basis are small, but on a large project these small things (unfairly labelled as sugar) compound into large scale effects like a cleaner, leaner code base.
Part of your comment might be related to why CoffeeScript gets blowback -- there's an implication that if you're not using CoffeeScript, then you're not an expert.
I can see how it would give that impression due to taking a high-visibility feature in significant whitespace from Python, but other than list comprehensions, much of the rest is taken from Ruby:
Implicit returns, new conditional keywords (which don't use a Python-style : to signal the end of the conditions) and postfix conditionals, the @ operator, the ? suffix analogous to nil?, #{} for string interpolation, Ruby-style switch and (sometimes) optional parentheses can all result in very Ruby-like code, with the introduction of so many inconsistent ways to express the same statements.