I am not sure it is possible any longer for JS to avoid getting larded up with a bunch of features from other languages, due to the popularity it has achieved. But one of the things I used to like about it was its relatively constrained feature set. (I would almost say simplicity, but some of the wackier aspects of the language prevent me from going that far.) Now we have things I’m not sure anyone even uses like Symbols.

(Please don’t tell me I can just constrain the code I write to the subset of features I care about. We all read more code than we write.)