> Payment processors have to deal with significantly more problems due to the nature of porn games and chargebacks.

This is commonly repeated, but doesn't hold up. Chargeback fees (especially for card-not-present transactions) are paid by the merchant and are simply increased (with reserves required) for high-risk accounts. It also wouldn't make sense to target hyper-specific niches if it were really about chargebacks, they would go after all of it, and go after things like the CS marketplace.

But the biggest giveaway IMO is that they do not allow, e.g., Steam selling these games crypto-only. It's either remove them entirely or remove credit cards entirely. If it was really about specific titles having high fraud/chargeback rates, selling them some other way would be fine.