Individuals make that decision, just as they do when it comes to democracy as a whole. That's the point of freedom of speech: we can't have an authority on the truth.

The alternative is you aren't allowed to dislike and refuse to patronize someone because of their actions, which is obviously absurd.

Everyone agrees people shouldn't face disproportionate responses, so arguing for that is nothing. Either you need to argue there are general things causing that (e.g: not looking into context, retractions, etc... before making judgements, which is a real problem) or argue the ethics of the particular situation, which is unique to a case.

Almost always, I see "cancel culture" used as a shield to avoid having to defend the actual harm done.

Maybe you could provide a solid point of "the actual harm done" when someone says "there are nazis in the army"? (if it's true)

If it's false, maybe you can claim slander on an entire army? Even the law doesn't protect anyone from that...

The harm done is very clear: the indented implication that Ukraine is controlled by Nazis is intended to justify Russia's illegal and unjustified war which is about control by Russia, and helps no one in Ukraine.

If it's false, then sure. But if it's true, then those hiding this fact are actually supporting Nazis.

Don't you think it's important to have as many sources of information as possible to verify this?