Probably because the original "politics as mindkiller" article is about avoiding non-critical politically charged examples, and says nothing about avoiding any and all political discussion. In fact, it says at the end that it's ok to talk about politically charged subjects.

(Of course, the whole thing is just EY's opinion, and we're certainly allowed to have new norms like "no politics ever". But the original post frequently gets invoked as if it says things that it in fact says the opposite of.)