People see to want to know why others have downvoted them. Here you go - here's why I downvoted your comment:
You have rushed to make assumptions and judgments here and then insulted the OP. I don't understand why you felt the need to make a personal attack. It's unwarranted. The OP had some nice, encouraging words for the FB Purity guy and then here you go making disparaging remarks.
Although you might not agree with his point, there's no need to say "Not true" and then insult him.