This question already has an answer here:
With concerns about a question being closed as "too broad" in the back of my head, I tend to ask questions such as this one about metropolitan airport codes when I have a specific example of an airline, area, hotel etc. in mind; in that case I was primarily focused on the Bay Area. However, the helpful answer I got was also more generally applicable to other parts of the world. The question is still titled "Is there an IATA airport code for the Bay Area?", but it would seem to me to be to everyone's benefit for me to generalise it by removing specific references to the Bay Area and asking the question about everywhere in the world.
Is that a helpful and wise step, or would that violate the "too broad" policy? In this case, a broad answer would seem sensible (after all, the list linked to in the answer covers the whole world), and theoretically, one could otherwise end up with this question about every metropolitan area, with basically the same answer.
Note: I am specifically talking here about editing my own questions, not those asked by others. I am not sure if the answer would be the same, since others might have had different motivations behind the asking.