True. Contentious or not, there's no need for personal attacks.
+1. I have not gone into that thread and I won't.
There's a couple topics that I don't generally like to discuss, politics, religion, and money. It's often tempting for me to chime in, rebut an argument etc... when someone posts publicly but unless it's a close friend and we're chilling in person, I refrain.
That said, I also strongly believe in the freedom of thought and expression, as long as there is no personal attack. That's the red line.