What is unethical about not wanting to carry speech you don't agree with, is inflammatory, or outright misinformation?
What they deem outright information may in fact be true. And even allowing clear misinformation (1+1=3) is important. We need people to learn to process information not protect them from it. Using 1+1=3 analogy, wouldn’t you want people to rally around tooling people to learn math?
Flagging misinformation is attempting to educate people.