The most negative people calling others homers is an age old tactic here. It's just a way to justify their negativity that usually ends up being proven wrong.
I feel the same. I'm fine with people being negative or saying the players and team sucks, but after about the 100th post saying the same thing, they become narratives (IMO false narratives), just due to the sheer repetition of people saying them, that's when it starts to be annoying and needs to be balanced out with a different pov, and if available facts to correct the record.
As you allude to it's usually started with people stating their opinions as objective facts.