Earlier quoted context omitted.
Er, no, I am fully aware that LLMs have always been non-deterministic.
Your argument seems to be that a statistically-improbable number of people all experienced ultimately- randomly-poor outputs, leading to only a misperception of model degradation… but this is not supported by reality, in which a different cause was found, so I was trying to connect your dots.
Combining these things in the strongest interpretation instead of an easy to attack one and it's very reasonable to posit a critical mass has been reached where enough people will report about issues causing others to try their own investigations while the negative outliers get the most online attention.
I'm not convinced this is the story (or, at least the biggest part of it) myself but I'm not ready to declare it illogical either.