Can only guess, since you haven't given the Chinese characters:

"Turns out that this piece of rubbish is actually an article penned by a famous writer. It's a real eye-opener."

Gou pi bu tong: crude but often used phrase, can mean such things as: "You don't understand shit;" "You're full of hot air"; and when used as an adjective phrase (as here), "nonsensical," "empty."