It certainly isn't. It also isn't always the second someone does something wrong they're out the door, friendship over and fuck them. Unless it's incredibly serious, possibly direct harm or something so unforgivable.
Have you ever causally read an advice thread on GAF about family/friends or work colleagues that might have made a mistake or possibly have an iffy political or social stance? Nuance is lost on some people. It's straight to dial nuclear the second someone has a bit of a social disagreement.
I honestly don't know how anyone could be friends with some posters on here. You'd literally need to be a clone. 100% the same. Life is full of social landmines and friends and family erupting in disagreements. You tend to take the overall package of a person into consideration before catapulting them into the sun never to speak to them again and hold a hater boner till the day you're dead.
Greg called Colin out, Colin might disagree, but that doesn't mean Greg hates Colin now, Colin hates Greg and everyone hates everyone. Greg's lived with Colin, he'll know what he's like. It was most likely a combo of yes, calling him out, but also trying to calm down some of the flames of the internet losing its collective mind. As I framed it earlier this has erupted/spilled over into the internet culture war more than anything. Projection galore, people hating other people and taking opportunities to air their own personal grievances off the back of Colin and take pot shots at others who don't agree with them. I seriously doubt anyone really gives a shit this much about Colin. Half the people involved probably don't watch KF or even care about it.