Allow me to correct your corrections about what is actually going on.
In other words, let me fact-check your fact-check.
You beg the question by claiming that only "self confirming nonsense" and "propagandist nonsense" will be hidden from the public, calling any position that sees cause for concern about censorship "a pretense." However, you offer no evidence for your claim that only these types of content will be affected. In fact, Snopes and many of the other fact-checkers have been shown to be politically biased themselves, and they certainly don't limit themselves to debunking propagandist nonsense. If we take their past performance as evidence of what is likely to happen moving forward, we will see, just for example a conservatives shut out of the public conversation for saying exactly the same thing a liberal is given a pass on. For claiming that nothing but truly egregious content could possibly ever be filtered, you receive 2 long noses.
Your claim that "the argument has now deteriorated into the surreal position that no-one (e.g. Snopes) should dare even post corrections to politically motivated lies" is blatantly false and receives 3 more long noses. Pretending that the fact-checkers have never told politically motivated lies themselves—only corrections—gives 1 extra long nose. Your claim that the argument goes so far as to say that nobody should promulgate corrections to political lies is exactly the opposite of the truth, earning you 4 more long noses. The whole goal is to leave every lie open for correction, by anybody who is able to offer a compelling case and back it up such that people trust the correction.
The objection is against setting official truth-setters, because that divides people into two classes: 1. people who are allowed to think for themselves and check facts, and 2. everybody else, who must, for their own safety and well-being, have the first class filter what they read.