If Joe McCarthy operated through Twitter instead and privately convinced private companies/individuals to take action on marked individuals, would it be any less of a cancellation? Government backing certainly made it worse, but I'd think many disagree with McCarthyism because of what he did rather than how he did it.

No politicians today participate in cancel culture? I doubt it.

Regardless let's use a non political example. I assume if the issue is "force of government" then you were 100% okay with the Hollywood Blacklists? (Generally accepted to be part of MCCarthyism) After all that's basically analogous to deplatforming and it was private companies that were doing it with no force of government. Do you support the Hollywood blacklists?

I disagree with the studios' reasons for doing it (it was dressed up as a patriotic move, but was fairly thinly-veiled anti-labor action intended to disrupt the growing trend towards unionization in the entertainment industry).

But as political affiliation was not (and for pretty obvious reasons, probably should not be, California's subsequent state-level decisions notwithstanding) a protected employment class, they certainly had the right to do it. The HUAC is a different story.

(You take away the studios' right to blacklist communists and you take away their right to blacklist KKK members at the same time. It's a step I'm not personally comfortable with. And especially in the modern era, when the technology is cheaper and more decentralized, I prefer to see the solution to such things be competition to the Hollywood system instead of tying Hollywood's hands on political matters.)