One thing I've seen around on the internet, mainly with English speakers, is how people care so much about language mistakes. Misspelling something, mispronouncing something, using the wrong form of a word, can be reasons for people to see someone as dumb or get angry at them, because they made an 'error'.

Simply, stop caring about it so much; Here's an interesting fact, the main purpose of language is for communication, if someone says something to you and you clearly understand the meaning of what they said, communication happened (even if you're the pedantic douche who will pretend to not understand, you understood, you are only doing that to be an ass) and anything else is detail, trying to 'one up' them by correcting for the sake of correcting is plain dumb. The only time error matters is when it actually makes something harder/impossible to understand or ambiguous, when communication doesn't happen (using 'the technically correct therm' while everyone uses some other term you don't like is an error because it is making it harder to undesrstand what you're talking, and with that I have some spicy ranting for some day)

One error I see too much happening and pointed out, the "they're there their", what about, someone is not being dumb for using the wrong one, it's just that if you learn a language trough sound more than text, it can be harder to differentiate words that can sound exactly the same. Althought these can fall under the 'making it harder to read' way, so, to actually help people instead of doing a "*they're", here's how you use them: "there" means "in that place", for example "he is standing over there". "their" means the possesive of the third person plural/neutral pronoun, for example in "Jesse and Lake have a red car, their car is red". "they're" is the contraction of "they" + "are", as in "Jesse wants to go to sleep because they're tired".1

Moving to being more egocentric, at school there was an entire topic on my portuguese subject about the variation of language, and how it has to be respected, not just accents from different places, but also on the way the person learned the language and their skill level, no one is obligated or should always speak with the mastery of a writer for the sake of being 'right' over being context aware or not being an ass.

  1. Then there's the hell of "through tough thorough thought though", WTF