The abstract of the meta-analysis might help you understand what they found

The notion of problematic pornography use remains contentious in both academic and popular literature. Although the mental health community at large is divided as to the addictive versus non-addictive nature of Internet pornography, substantial numbers of individuals report “feeling” as if their use of Internet pornography is problematic. The present work seeks to construct a model related to problematic pornography use that is clearly derived from empirical literature and that provides directions to be tested in future research. The focus of the present work is on those perceptions as they relate to the overarching experience of moral incongruence in pornography use, which is generally thought of as the experience of having one’s behaviors be inconsistent with one’s beliefs. To this end, we put forth a model of pornography problems due to moral incongruence. Within this model, we describe how pornography-related problems—particularly feelings of addiction to pornography—may be, in many cases, better construed as functions of discrepancies—moral incongruence—between pornography-related beliefs and pornography-related behaviors. A systematic review of literature and meta-analysis is conducted in order to evaluate support for this model, and the implications of this model for research and clinical practice are discussed.