Actually curious to hear what people on here think about this.
It's a real problem, but mostly just for the sort of people who might sign on to a letter such as this: elite think tankers, academics, and columnists, who would love nothing more than to be able to continue spouting unsubstantiated nonsense with impunity.
If your livelihood is throwing opinions into the Internet wind, then of course cancel culture is an existential threat. As these sorts of people now tend to be extremely online, every little barb and retort pains them disproportionally, too.
For most of us, it's just a distraction. If you're not famous on the Internet, you can't be canceled to begin with.