Facebook never allowed porn or even artistic nudes. YouTube only sometimes allows nudity/sex. Twitter and YouTube started scrubbing media drops from ISIS and ot

Facebook never allowed porn or even artistic nudes. YouTube only sometimes allows nudity/sex. Twitter and YouTube started scrubbing media drops from ISIS and other violent Islamist groups before Trump even had the nomination. They did so after bipartisan calls for social media to deplatform terrorist propaganda. Reddit also cracked down on Syrian civil war media around this time. The videos were often gruesome propaganda and evidence of war crimes at the same time. The reason people called on social media to remove this material instead of making it a job for law enforcement is that First Amendment protections are very broad. Praising ISIS or sharing "inspirational" videos of them killing government soldiers is not a crime if it doesn't also call for imminent lawless action. But few Americans of any political affiliation want such material to spread freely online, so it has been suppressed by other means on major platforms. I'm not endorsing or condemning how these platforms behave. I'm just pointing out that they have long suppressed material that the First Amendment protects. The timeline of moderation well predates the Trump presidency.