Not really. Mob mentality is the root of cancel culture, and death threats are frequently a mob's calling card. Also, I'm not sure just how clear we are in defining cancelling. It's convenient to accept light cancelling (why, we just don't allow his kind on facebook) while downplaying the darker side.
That's still a textbook association fallacy. Which is to say, broken logic. That's what "fallacy" means.
What the BS peddlers have been doing through all this thread has basically been a texbook example of this:
P1: A is a B
P2: A is also a C
therefore
C: Therefore, all Bs are Cs
In this case
P1: some example of a tweet is a case of "cancel culture"
P2: same example of a tweet is morally or legally wrong (e.g., by being a death threat)
therefore
C: Therefore, all cases of "cancel culture" are morally or legally wrong
Or in more layman terms, for those who can't follow all this newfangled logic (after all, it's only been around for 2500 years, some people may still not have gotten the memo
): almost anything can be associated with anything. More to the point, just about anything can be used in conjunction with something immoral or illegal. I could use a car or pickup truck to carry the explosives for a terrorist act, like Timothy McVeigh did. I could use a fork to stab the wife. (And in fact, fork wounds tend to be worse than knife wounds.) I could sic my dog on my ex. Etc.
But it would take someone really stonking stupid to deduce that if some people use cars to carry around bombs for terrorist attacks, then the whole driving culture is to blame. Or that the whole pet-owning culture is to blame for the last one.
Even in the case of death threats, people have sent them for pretty much every reason imaginable. E.g., some people literally sent death threats to, say, Stardock over their games' bugs and balance issues. (That's not a hypothetical, btw. I'm using a real company name because it's a case that actually happened.) E.g., anime companies routinely receive death threats: it turned out at one point that one single woman had sent literally 3,852 death threat emails to a bookstore chain that also sells anime and manga, while another chucklenuts escalated from sending death threats to Kyoto Animation to an actual arson attack that killed IIRC over 30 people.
But, again, it would take a complete idiot to deduce that if some people use death threats in conjunction with wanting a game patched, then the whole culture of expecting bugs to be patched is to blame. Or to blame the whole culture of cartoon fandom, because SOME are outright deranged fanboys or fangirls.
It's downright stupid to blame a whole category X just because sometimes it's done in conjunction with illegal activity Y... and a lot of times not.
Pretty much ANY movement or activity will include a number of deranged people, if it's grown past being just a couple of people. If nothing else, by sheer probabilities alone, 1% of the population at any given time are outright schizophrenic. You can find deranged people in everything from "cancel culture" to football to Star Wars fandom to politics to stamp collecting. ANYTHING you don't like can be painted as evil by picking some extreme example and pretending that everyone else in it is just the same. It's in fact THE most prevalent technique of dishonest and bigotted idiots and the like: try to handwave that every Muslim is just like Osama, every atheist is just like Stalin, every black rights activist is just like <insert deranged black supremacist>, and in this case apparently everyone who's ever criticized someone on twitter is EXACTLY like the few guys who've escalated it to death threats.
But then I guess when some people can't make their case otherwise, they also feel they're entitled to do fallacies and/or, as I've said before, to flat out lie about their premises.
