The word "godlessness" is a little bit tricky. Atheism is the absence of belief in gods, while godlessness is the absence of gods, so I guess I will be answering about more on the issue of godlessness than atheism in this post.
Based on the definition, I think Mr. Pasco here is a little bit bias. First, there are godless religions like Buddhism and Jainism for example. Now, don't tell me Buddhists or a Jainist indulged themselves with pornography, fornication, abortion, adultery, homosexuality, lying, and blasphemy? On the contrary, Buddhism and Jainism are the most peaceful of religion.
Second, now when did secular living, politics and arts became an excuse to pornography, fornication, abortion, adultery, homosexuality, lying, and blasphemy? Mr. Pasco (again) didn't give us a good argument, other than biblical eisegesis.
Remember that religious belief is irrelevant when it comes to arts, politics and education. There is no advantage nor disadvantage.
Downside? Not of any we can think of.