This specific question
I don't think the question is asking for recommendations of VCS. Instead, it is asking for knowledge about the existence of VCS: the OP has a problem about collaboration, which he wishes to solve with a program. VCS is likely not the only way to do this, so other answers may be valid as well.
However, that does fit into the category of Idea Generation (which is not a close reason we have here, but other sites do). Idea generation questions are banned on other sites because there is no objective way of judging which answer is the best: one recommendation is as equally valid as another.
Do we want these?
In my (strong) opinion, no. If we allow these types of questions, we'll get license-recommendation questions... Noting this message in chat, those will (sorry, but they will) lead to endless debates and arguments about which license is better than another, which is not something we want to have to clear up.