I know nothing about the questioner so this is just a guess, but if English isn't his first language it's possible that he isn't up to speed with some of the more nuanced idiomatic usages. No matter how proficient a speaker sounds with straighforward word choice, ordering and grammar, the idiomatic nuances are often the last things to be mastered, and very often such nuances are never fully mastered.
That doesn't, however, excuse what seems a pretty blatent attempt at manufacturing a controversy and nor does it explain why he doesn't acknowledge his misunderstanding once it is explained to him. All languages have their own idiomatic nuances so no-one should find the notion alien, even if they aren't always familiar with them in a non-first language.