Not much, I would say. Something important in CoffeeScript is "everything is an expression". That was a feature in Lisps, in Haskell, in Rust, but would never be default behavior for JavaScript. JavaScript is becoming less odd with modern features, but still far from being liked.

a bad aspect of CoffeeScript I see is "it's not an industry language". too flexible, insufficient integrations with standard tools, slow fixes and new features. The industry definitely need as lot of features for pushing and also controlling work.