I think we do care, to an extent. The goal of SE sites is to provide an archive of good questions and answers foremost, but a secondary goal is to get individual users the answers they are after.
In cases like you've described, I would advocate for taking a firm hand in editing the question into something reasonable based on whatever context clues are available, provided that you can make a case for there being a single obvious question in there somewhere. Try, as best as possible, to keep the asker's intent in mind, but do prioritize the validity of the question over that intent if there's doubt.
Usually in these cases I'd leave a comment explaining that I edited the question but couldn't be sure I fully understood the asker, and request that they clarify my edit. This reinforces (especially to new users, who are usually the ones responsible for these kinds of questions) what happened to their question, that they can also edit, and various other details about the operation of the network.
However, if a question is really bad, to the point where there could be multiple equally-valid but unrelated questions in it, or you aren't confident what the intent is, please vote to close as unclear instead. Once a question has answers it's much harder to make major edits align without then doing somebody a disservice, so if that seems like it might happen it's better for the long-term health of the site to put the question on hold for a while rather than let ultimately unrelated answers clutter up the post.