So I recently asked a question about the new Diablo expansion. I know that the content isn't playable yet, but it's already in the game (files). I personally got a flail which is one of these items (not really useable but available) and I even mentioned in the question itself.
What I don't really get is why it was closed. This post says that
If a "pre-release" question about a game can be asked and answered without speculation because an alpha/beta/early version exists, regardless of the number of people who are/could be in possession of said game, it should be left open. (Unless there's some other reason to close - bad questions are bad questions, regardless of topic/game)
And there was a closed beta of D3ROS for a pretty long time. Now since it was closed for being off topic because the game isn't released yet, I don't really get when a question is closed as off topic because of unreleased content. Also as already mentioned all the files are existent, so a dataminer could really find it out. And even if noone on arqade has ever played the beta, a random beta player could've surfed the web and he could have registered an account to answer this question.
There are actually some other games that work similar with releases, some of them being League of Legends (Champion is available in the client but not buyable) and World of Warcraft (Prepatch of an expansion where you can't access the new regions but they are there). How should such questions be handled in general?