“Porn addiction” is actually more like “porn compulsion.” Colloquially, compulsions are often called addictions (“video game addiction” is also a compulsion, an addiction would be something like crack) but it’s worrying with porn because it’s treated as an actual addiction, and the theories behind the modern worries about “porn addiction” are pseudoscience by unqualified people (Gary Wilson and Marnia Robinson) with a very strict idea of what a sexual relationship should look like.