A situation has come up on Drupal Answers that I wanted to bring to the larger SE audience. I am not asking for how to solve our particular problem, but how this type of problem should be handled on SE in general.
For those that don't know Drupal Answers, it is the SE site dedicated to an open-source content management system called Drupal. The site deals with all sorts of questions, from code (i.e., developer oriented) to users (i.e., site users / builders).
You probably could have put two and two together there, but bear with me.
DA discourages the use of version tags, much like many other SE sites. They should only be used when the version number is specifically needed to answer a question.
For example, "How do I create a user?" doesn't need a version tag; it's a rather generic question from a Drupal standpoint.
A question like, "How do I do an EntityFieldQuery for users who are blocked?" probably needs a version tag.
A little over a year ago, Drupal 8 came out. This version was a radical rewrite of the software. This means that a lot of questions have radically different answers depending on version <= 7 and >= 8.
For example, "How do I add a JavaScript library to my theme?" is a generic question, but two totally different answers for Drupal 7 and 8.
Why is this a problem? We have about six years worth of questions and answers. A lot of questions that are starting to come in are question duplicates, but would have radically different answers. Nearly every question has the comment now "What version?" and someone edits this into the question and/or tags it, even on the generic questions.
There are two options that are being discussed.
Close as duplicate, and add the Drupal 8 answer to the older question. The problem with this results in a lot of closures, and it makes finding answers to current problems difficult.
Allow the new questions, and tag them. The problem with this is that we now have lots of nearly identical questions, other than tags. And, we have lots of old questions w/o version tags. And when Drupal 9 comes out, it would require mass tagging, or worse more versions of questions if Drupal 9 is radically different than Drupal 8.
I have tried to lay out the situation, and provide some (contrived) examples. Please don't dwell on the examples above; they are really just to try to illustrate the problem.
What should a software-related SE site do when a drastic change happens between versions that would potentially cause a split of questions between old and new versions?