Reddit writing

What gets me is the sheer amount of people on Reddit who can't write, who don't understand grammar and punctuation. Unnecessarily adding an apostrophe in 'it's' is particularly common. Confusion over there/their/they're. And there's the horrible trend of misusing 'of': 'it's not that big of a boat' etc. What does 'of' mean in that context???!!!! Ahhhhh!!!!!