This is a lot more sinister than “cancel culture”. Cancel culture was when someone with a platform expressed a bigoted opinion, gained a lot of attention, and caused a backlash.
What these people are doing is actively and openly organising to encourage others to seek out, denounce and victimize anyone anywhere who doesn’t toe the line. It’s a modern-day Stasi.
I once worked in a European office of a big US company a while back where I negotiated a fair salary, they agreed, and then on the first day the contract arrived and fully 25% of it was a "bonus target" that I was assured everyone always got every time so I shouldn't worry about it.
Inevitably, it was the first thing to go as soon as a new CEO came in with the task of improving Earnings Per Share, giving me an instant 25% pay cut. What's shittier is they announced it after the period it applied to, so it was a retroactive 25% pay cut as well. Luckily I wanted to leave anyway for other reasons, so I took them to a tribunal and got paid, cause you can't pull that sort of shit in Europe. My US colleagues didn't fare so well.