The best way to challenge something is to make a broad statement that is totally unsupported by any facts and then base your argument on that broad statement. By the time people are finished with your argument, they forget that you never supported your underlying thesis.
I am not Roman Catholic and I'm not sure the Bible mandates celibacy for the priesthood. But, considering the large number of priests and the very small number of ordained pedophiles I am sure there is no basis in the above assertion. I have never heard that the ratio of pedophile priests is higher than the ratio of pedophiles in general. But to accept this author's point, you would need to believe it was. I am sure that a pedophile priest is more newsworthy than a pedophile in general so it can seem that becoming a priest makes one a pedophile.
Of course, we're also not evaluating how many priests engage in illicit adult heterosexual activity. That's because the author has an axe to grind.
If the Catholic church needs to take action, it needs to do a better job of protecting its boys from the few priests who do fall in this manner. It also needs to provide better help to the priests who believe they are falling - to let them know they can request help without fear of reprisal and receive the full forgiveness of Jesus so they can get on with their lives.
Of course, the Church needs to make sure she believes the requirement for celibate priests comes from G-d. But if she is sure, then she needs to stand by what G-d has said no matter what idiots like this author believe.
Shalom.
Catholics do not deny harsh realities. Here's two things I have been studying lately: