Knives have been used to murder people. They are absolutely harmful.

Your grossly reductionist argument doesn't really add much to the discussion.

You are very quick to dismiss a completely valid point, people are careful with sharp knives, and for example, generally don't let children use them, they aren't allowed on airplanes etc.

How many people have a similar view of facebook as dangerous?

It's the type of use that makes a knife dangerous. Everyday people use knives to prepare and eat food but don't think what they are doing is dangerous.

Everyone respects how dangerous knives at at least - you know not to play around with them and you know how sharp their edges are. People don't (I really really hope) realize how many lives they're endangering by passing on misinformation. America is one of the most individualistic and tech literate countries in the world and it's suffering terribly during this pandemic from absolutely atrocious vaccination numbers.

All the knives in the world aren't under the real-time control of a single entity.

Should we ban all telecoms too? I mean people used phones on networks to commit genocide as well. While we're at it, we should ban iPhones as well because they used them to communicate. What a stupid argument.

Facebook is harmful, but this is a bad argument for why. The knife analogy is a good counter example.