Should an accusation alone have that effect?
The point is, many lies are a particular kind of bad faith. You can point out to the guy who, say, believes Antoine Béchamp is the last word in medicine, that he is misrepresenting Béchamp in the past, let alone misrepresenting science in the present, and that guy will argue that it is the very predictable pattern of your fact-based attempt to disprove him that is evidence of your perfidy.
When you know that person is making that argument knowing it to be false, there is no point in accusing them.
The only thing you can do is tackle the "alternative facts" as misinformation rather than as an attempt to deceive.
Because those who argue in bad faith claim injury in bad faith too. "Misinformation" is a more dispassionate approach.
- accusing someone of lying has no restraining impact on the person or the lie, and indeed where it might have a magnifying effect
or
- the lie is being shared by someone who has been lied to and does not know it; they aren't a liar but they are misinformers.
Calling the "Covid hasn't even been isolated" misinformation a lie, for example, requires knowing that the teller is aware they are lying. They could simply be credulous.