The problem is not that porn is unrealistic, but that it's the only depictions they see. They need to see normal depictions of sex, also, and it needs to be made clear that porn is no more a realistic depiction of sex than Hollywood is a realistic depiction of life.
You and I probably do have an unrealistic view of fighting because we're only exposed to it in action movies that portray it unrealistically. It's not a problem though because we're not gonna fight and it won't matter if we have the right idea of it or not.
The article does not claim empirical evidence but cites someon that has been working and publishing on the topic. I wonder why this should be wrong by any journaliszic standards.
Is there any scientific evidence that the anecdotal evidence by this psychotherapist is wrong? BTW: the German Minister for interior currently actually wants to decriminalise some child porn offenses again because it would mostly target children themselves. I have the feeling that the debate is not out of balance in Germany, but still rather pragmatic.