"If Visa was aware that there was a substantial amount of child porn on MindGeek’s sites,"
It would be reasonable for anyone to believe that a registered business that is a major operator is following the law. If they are not, then why hadn't the government intervened? As a user when you go to pornhub or any other site with the legal footnote about age, you have the reasonable expectation that you aren't going to get child porn.
"substantial" is doing a massive heavy lifting here as well. I don't really buy that somehow Pornhub has more CSAM than Youtube, Facebook, or Twitter. They were targeted for ideaological reasons.
It would be reasonable for anyone to believe that a registered business that is a major operator is following the law. If they are not, then why hadn't the government intervened? As a user when you go to pornhub or any other site with the legal footnote about age, you have the reasonable expectation that you aren't going to get child porn.