“English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts.”
This is the first sentence on the Tour page, yet we are overwhelmed with first posts from non-native speakers or those with poor education asking proofreading questions or basic questions about the language. Most of them get closed (I spend my 20 close votes each day on them) but are visible long enough for other similar posters to think this is norm.
What to do?
Prevent them being posted in the first place.
How to do it?
If you think of these posts as a sort of spam (I know they are not literally spam), then what one needs is a ‘spam filter’. Like on gmail or whatever. So how do real spam filers work? Presumably by ‘training’ or coding them to recognize certain features of emails that indicate they are spam. Are there features of off-topic posts that could be used in a ‘spam filter‘? Many of them contain poor English, so perhaps a grammar checker could be used. Other features might be numbered lists and embedded images. And one could use AI (Artificial Intelligence) to train a program with examples of on-topic and off-topic posts.
Who would do it?
A bit like belling the cat. But surely someone knows somebody’s cousin who has a boy-friend that does that sort of thing. Please, before we all drown.