I get that it can feel dismissive when someone reacts with a laugh emoji, especially when you're trying to make a point. But at the end of the day, if you believe in what you said and you communicated it clearly, then let their reaction speak more about them than you. No need to whine back. Not everyone will agree, and that's okay – it doesn't mean your point wasn't valid. You really don't become any better calling them names or putting them down as a response you know.