Yes, emotionally manipulative language is effective, but it doesn't have to be. Train yourself to look for it, and then choose to reject it. When you see someone appealing to your emotions instead of your reason, recognize what they're doing and call them out for it. That's especially true when they're saying things you agree with, because that's when you're most vulnerable to manipulation. We each have the responsibility to reject people who try to manipulate our emotions and tell them that's not acceptable. We also have the responsibility not to stoop to doing it ourselves. If your arguments are sound, they can stand on their own without emotionally manipulative language. If you find you can't make your arguments sound convincing without it, that's a pretty good clue there's something wrong with them.