Caveat - I proofread and edit for a living, so this is a particular bugbear of mine.
Literally every thread I've been on today has been derailed by someone making a statement that is clearly contradicted by information from the OP, or jumping down the throat of a PP because of something they never wrote, or asking questions that are already answered, and then getting their knickers in a twist about it.
I can understand skim reading, i do it myself, but if you're going to start hurling invective at strangers online, surely you'd double check what you've chosen to get mouthy about first? Or are the type of people who froth at the mouth over things that are nothing to do with them just not that good at reading comprehension?