In order for AI to become a more effective tool for detecting hate speech, it must be able to understand content the way people do: holistically. When viewing a meme, for example, we don’t think about the words and photo independently of each other; we understand the combined meaning. This is extremely challenging for machines, however, because it means they can’t analyze the text and the image separately. They must combine these different modalities and understand how the meaning changes when they are presented together.
Facebook is going for the really hard case, where non-hate images and non-hate text combine to induce hate. They already have a text-only system.
[1] https://venturebeat.com/2020/05/12/facebook-is-using-more-ai...
So when we say big players, do you mean FB or do you mean the National Govs?
Side note - the CCP also employs manpower to handle the task, so its not just ML, my point hovers on the ML aspect of it.
1) Slang evolves.
2) Combining two languages, especially under-resourced languages, mean that a chunk of words fall outside the range of a hate-speech lexicon.
So maybe in languages which have huge resources devoted to it (English), its easy to figure out, but I don't know how well covered the evolving edge, and the code-mixed (language mixed) edges are.