The correct way to organize social media is in federated way. Each server only holds on average a few hundred or few thousand people. Server moderators should be legally responsible for content on their server. CSAM on social media will be 100x suppressed because banning people is way easier on small servers.
Not many moderators will have to look at CSAM because the structure of the system makes is unappealing to even try sharing CSAM, knowing you will be immediately blocked.