Sure, but you do have extra context you
can make available on both ends, but that I'm assuming most don't even try to include.
E.g. if judging tweets for example you'd presumably do a lot better if you evaluated the tweets in context of followers and in context of past tweets - both recent and the accounts history. E.g. an account that posts white supremacy tweets regularly is likely to mean something entirely different if RT'ing a BLM tweet with "that is fucking awesome" than what someone with #BLM in their profile is likely to mean.
Part of the problem is that they're throwing away a huge amount of the state they do in fact have.
But I absolutely agree it's in general an unsolvable issue - I pointed to a story from my childhood elsewhere showing how trivially people cause problems for "The Decider": A childhood friend being forced not to call his brother names and switching to using names of cheeses.
Is "Edam" an insult or a food preference? You can't know without context.
And it needs to be very local context, because humans very quickly pick up on when you just start using a word to mean something else, so it doesn't even need to be any shared external state about the word, just a shared understanding of where the receiver might expect an insult coupled with an unexpected response that will then easily get labelled an insult. That unexpected term might well in itself be positive if the receiver expects criticism. "Awesome" and "I love it!" are perfectly good insults when the other party has just told you something where the appropriate response would be negative, for example.