"Cancel culture" is just a new spin on scapegoating, behavioral contagion, and public shaming, all of which have a very long history.
Because ‘sane people’ does not include your employer, who will throw you to the mob to appease them. In the US that also means losing your health insurance, so it can be a death sentence for you or your loved ones.
(I'll regret posting this when I'm starving in a gutter.)
They can't afford to do that, because this "mob" is actively dangerous. They will slander their enemies with all sorts of baseless accusations, call their workplaces to try and get them fired, manufacture false flag harrassment/cyberbulling and try to attribute it to them, etc. It's no different from the 8chan trolls - in fact they come from adjacent Internet subcultures, quite literally.
They are successful at making people's lives miserable through harassment like death threats and swatting, and unsurprisingly, those tactics are universally reviled.
Notable exception: Donglegate; a person was cancelled, then the person cancelling got cancelled - her company was DDoSed until she was gone*
Hilarious.
* well, that's what I want to believe because it's more interesting; it's possible backlash of people against first cancellation had it's part in that.
Just look at the death threats someone like Fauci is getting for doing his job and informing the public. Not that many people want to deal with being a public target to the worst actors in society.