If you claim to be very experienced in JavaScript but then say that you are ignorant of closures, then that's definitely a red flag. That language relies heavil

If you claim to be very experienced in JavaScript but then say that you are ignorant of closures, then that's definitely a red flag. That language relies heavily on closures, more than others, and almost every programming pattern in the browser involves capturing some sort of state about enclosing scopes etc. given the asynchronous nature of things. The inordinate amount of space the article devotes to complaining about 'credentialism' just reinforces the impression that the writer hasn't taken the time to know his tools/languages/frameworks at a deeper level, and is dismayed to have been found out in interviews.