There can’t be any of those things if there is no such thing as objective lies. You said that if someone can decide if something is a lie then bias is involved and that is wrong. So if I call you a pedophile you can’t say that is slander because that is your bias.
I can ask you to prove such an allegation. When you fall flat on your face to assert proof, I am awarded victory on the slander, and you pay the cost. Eventually, you are bankrupted and cannot continue the stupidity.
This is why you are against banning Russian trolls who spread mistruths because the judger of the mistruth will be biased.
I am against banning what you call Russian trolls because people call anyone they don't like these days a Russian Troll. I, myself, have been called that before and it is totally incorrect. People on this very board make repeated comments about paying folks in rubles and how Putin likes them, simply because they don't align with the thinking of the left. Imagine if you guys could ban those folks.