> For example: The npm package "is-even" depends on the "is-odd" package. (In case it's not clear, this is a real package, not a made-up example.) In most other languages, these would be bundled together into an Integer Utilties package, if they're not already part of the standard library. In NPM, they are separate packages.

People should not be using these functions at all, in any language, in a standard library or otherwise. To convert the even/oddness of an integer to a boolean in Javascript you can use !!(n % 2), which returns true for odd inputs, and false for even inputs. If you want to be extra explicit you can temporarily store the result of that expression in a meaningfully named variable. If it will just be used in a conditional, then the !! can be skipped.

Depending on a third-party package for this kind of thing is insanity. But the blame lies with programmers who use this package, not with the programming language.