Do we want to allow language-identification questions? If so, what requirements should we place on these questions?
I don't think simple Identify this programming language! questions should be considered on topic.
Our topic is programming contests and challenges. While we decided on multiple occasions to allow certain non-challenge questions that are related to participating in competitions or even creating them, I don't think this kind of question fits in the same niche
Even if the community can figure out in which language some blurb of characters does something sensible, it will rarely help to identify a different blurb of characters. So, although these questions are related to certain kinds of cops-and-robbers challenges, they cannot teach how to participate in them.
In many aspects, these questions are similar Decrypt this ciphertext! questions that are common on crypto sites. Crypto SE decided to disallow them.
Questions asking to identify a movies, games, etc. tend to include a text description of what the OP is searching for. People who remember similar aspects of the movie/game/whatever will be able to find the question with a search engine. Trying to google esoteric source code will usually be pointless.