Harley — the article doesn’t say one bad word about the Baptist church he came from. You are making a big leap in saying “I would suspect...” — we are not called to judge, especially when we know next to nothing about the author
Christianity isn't worrying about Satan, demons, or bad people. Rather it is looking inside one self for our little foxes that spoil the vineyard. Like the repentant tax collector who recognized HIS sinfulness and cried out, "Be merciful to me."
It isn't a leap (big or small) to say that if he is complaining about others, then he might have a issue within himself. This isn't judging someone. It is merely stating an observation that his attitude doesn't square with what scripture is teaching. Paul had no problem telling the Corinthians about things that was not right understanding.