What about people who aren’t from an identifiable non-dominant sub-culture and seemingly just guess between “your” and “you’re” or “it’s” and “its”?
I see where you’re going with this but it’s not what you originally wrote… and even then, there is, IMHO, a difference between dialect and error, or between prescriptivism in terms of dialect and what is not.
The word “Y’all” is an absolutely classic example of dialect being looked down upon by prescriptivists; the word is distinctly regional/cultural and is frowned upon by many, but there is no compelling reason why. It’s actually a useful word (and I say that as a guy who’s never used the word.) Conversely, I am unaware of ANY cultural marker associated with confusing there, their and they’re. You can’t say a person pointing out that effort must necessarily be attacking another person’s “culture” unless you can demonstrate it’s a matter of differing culture in the first place. Sometimes bad spelling is just bad spelling.
RickJay: What you’re saying has merit if you assume the person doing the correcting has some idea about how language works, which is clearly not the case if they’re a prescriptivist. That’s why I mentioned peeving: Being against the misuse of “your/you’re” and being against “the house needs washed” are two different things, but to prescriptivist peevers, they’re impossible to differentiate.