I thought he brought a hell of a lot to the house but I knew he would be evicted. Have to say people claim they dislike name-calling, bullying, horrible, nasty, hypocritical behaviour then proceed to behave in those ways themselves towards one individual which is far worse.
Mark is an extremely extroverted person. Extrovert traits include acting before thinking, little to no self awareness, company for company's sake, addiction to attention...and so forth. Being an extrovert does not make you a bad person nor does being introverted make you a boring person - people should learnt the difference.
Mark's biggest mistake was having little self-awareness and not knowing what to say to people, he was after all friends with everyone in that house and was constantly telling everyone what they wanted to hear. I know plenty of people like that and they are not bad people. As for his relationship with Christopher, evicted HMs have confirmed Christopher is a lot more vocal in the house than the edit suggests and always gave as good as he got with Mark. The man is a journalist, he's not stupid. These two had a toxic love-hate relationship but it was much easier for people to blame the bigger character who showed less of a vulnerable side.