>>511279084 (OP)They're doing it for three reasons, both of which are legitimate:
1) If that random youtuber misidentifies someone and adds them to the list, and that person is someone with money or a reputation, then he's defamed that person. Nobody is going to sue some random ass Youtuber with no assets, but they will sue a company with tons of VC capital like Discord. If Discord knows about this dude's list and permits it to exist as a bot, over which they have significant control, then Discord is an easy target for that suit.
2) Going along with #1, what happens if this guy decides to start maliciously adding people he doesn't like to his list? A lot of these anti-pedophile Youtubers are, themselves, scumbags and this kind of shit is rife in that community. Even if he's a legitimately good guy, why does Discord want to take a chance on it?
3) The tech industry has made the decision that the risk of them falsely flagging people/servers as pedophiles is damaging enough, both to the people they wrongly flag and to themselves, that they've more or less turned enforcement of this over to the Federal Government. If this Youtube dude thinks he knows a bunch of pedophile discord servers, he could report that to the FBI and they'd be taken down relatively quickly (assuming that's what they were).