The thing is, those costs are already built into their margins and they have acceptable thresholds for them. Do porn games in particular exceed that threshold? We would need their proprietary data to determine that.

My hypothesis would be that these games have much lower rate of these charges. The reason being that these sorts of games are already subject to stricter restrictions and parental controls. I would expect the strongest association with charge backs and fraud investigations to be with games that are recurring subscriptions (people forget to cancel) or micro transactions. Which could include both pornographic and non-pornographic games.

I would also expect to see spikes in charge backs for specific games at specific times. Like when. Publisher adds Denuvo or some other draconian malware, or when 2K decided to add launchers to their game that hurt Steam Deck compatibility, or when some update happens that ruins gameplay, or when some executive comes out and says something stupid. But those would be events, not trends.