@lamp religiosity correlates with "porn addiction" as opposed to porn exposure itself. This data doesn't mean it's a religious thing, it means that porn is not addictive in the sense that, say, tobacco is addictive, where you would indeed find a correlative relationship between tobacco exposure and future tobacco use.
Now, there's lots more research to back up * why* tobacco is addictive, but the point is that porn exposure doesn't even CORRELATE, and therefore data doesn't even suggest a potential fundamentally addictive nature to pornography. Compare this to the data on gambling, too, which *does* demonstrate a correlation between exposure and continued increasing use (and has pretty substantial studies in its own right to explain gambling's addictive mechanisms on the brain)
religiosity CORRELATES with the behaviours that are described as "porn addiction", but that doesn't mean religiosity causes it - it means people experiencing "porn addiction" struggles have some common factor with religious people that leads the data to correlate them this way. The morality crisis induced by religion especially (and sometimes also through other societal factors) is a suggested reason to explain that correlation of behaviour and belief, but the research that far is still ongoing. Who knows what actually drives the behaviours we see as "porn addiction" - porn itself isn't the culprit, it isn't addictive. The statistical data has thoroughly demonstrated this.