I don't think Chan was wrong to say what he said, but I do think he has waaaay too much faith in his fandom to be mature about this and not attack others. The internet took it too damn far, blew it out of proportion, and started rumors. Calling Chan a "misogynist" and "attention-seeker" is completely unwarranted. He has every right to be offended that his hoobaes didn't return his greeting. It's not like he was trying to start anything by indirectly calling out whoever he was talking about. Everywhere I can think of, it's plain rude to ignore someone who's spoken to you, especially if they're older than you. Even if hoobaes didn't bow, it's not hard to give a nod, a smile or a slight wave to show that they're not trying to be rude.
Then there's the fact that Chan is not responsible for his fans' actions. Some people were saying that he should've never mentioned it at all and I agree. The best course of action would've been to have a private conversation with the other idols and handle it discreetly. At the same time, he has a right to say what he wants just like everyone else. While he could've predicted this outcome, he can't be blamed for what his fans chose to do.
This is the most balanced take in the thread.