Right-wing, openly evangelical groups like Exodus Cry and Morality in Media, who have an explicit agenda to ban pornography and see this as an easy "next step" towards that end goal.

They are also the groups behind the closure of big porn sites like XTube, the short-lived purge of adult content on OnlyFans (one of the few battles they lost), and the scourge of age verification bills that are sweeping the US, UK, and Europe.

The goal with age verification laws is not to protect minors or fight CSAM (as much as they pretend it is) - it's to make it expensive and difficult to legally serve content that they disapprove of, producing a chilling effect. Note that the content they disapprove of is not limited to pornography, which is why many of these bills have such vague language that can apply to other things like information on abortion, or LGBTQ+ themed material. This is not an accident; the supporters of these policies are quite open about their intention.