Picture the English class of the future where individual words make up only 50% of the working language and the other 50% are contractions that can mean whole statements.
I don't think so, every now and again there is a big hooplah in the news about this sort of thing being used in exams, but like my English teacher said back when I was at school, in subjects other than English, the language you use doesn't matter too much, as long as its readable all that matters is the content relating to the actual subject.
But in English you are expected to use a formal writing style, because, duh, it's an English class and that's the entire point, even using more accepted slang and colloquialisms would get you marked down.
She said that's pretty much always been the case, it's not a modern development.