Like politics and religion, I usually don't weigh in on these types of discussions. However...
Seems to me it takes more effort to say something nice than to say something rude. A rude answer is generally the first thought that one has when confronted with an opinion that differs from one's own opinion. That's human nature, to respond spur-of-the-moment. It takes some effort (whether a nano-second or longer) to step back, look at the message to which one is responding, and come up with a response that is both thoughtful and thought out.
Good rule of thumb...respond to others as you'd like to be responded to. Sound familiar?