The phrase "Cancel Culture" is designed to be tough and fearful. "There's a Culture that they (you know who they are) have where they crush...kill...Cancel those unlike them!"
Great for a moral panic, but in the end, all you see standard left wingers doing is saying "WWait, why isn't Trump 'cancelling" sports leagues, sugary drinks, and the like? And how are we "canceling" things we never even said anything about, much less organized against?" And the answer is, as I said, it's not a coherently defined term.
ETA: there's no *massive* disagreement that, say, sometimes people are fired unfairly for a social media post, some people who get attacked on Youtube for screaming and howling in public are really just having a mental illness episode and need help - although where these lines are drawn, exactly, is debatable. But adding "culture" to what moves it away from any individual boycott, and into the horrifying idea that there's some unspecified, but clearly *implied* mob that just goes around seeking revenge for petty offenses, something like a volcano god or dragon that can only be appeased through sacrifices or slaughtered - an ascribing of ill will to what are, rally, events that are effectively unrelated when you examine them.