I was under the impression that "usefulness to the asker" was good enough for a Q&A site. It appears this isn't self-evident, however.
it is, if the title of your site happens to be Yahoo Answers.
TL;DR version -- questions about things you can't remember suck... hard.
I'll just ctrl+c, ctrl+v from my edited gaming meta question.
Mapping these ['help me identify this game' questions] to existing close reasons, there are two that fit.
Too Localized. What value do these questions have to anyone else on the planet, other than the one person who asked? In other words, what internet user is going to be searching for and finding information about a game one person vaguely remembers playing, as described in generic broad "um, I think it had.." terms?
Not a Real Question. Half-remembered descriptions of a game you vaguely remember playing, does not a real question make. This wouldn't be tolerated on any other site in our network. Unless the asker has demonstrated and documented that they've invested substantial effort to find this game, and given us something concrete that provides us with a reasonable chance of actually finding a game, it's simply not a real question -- it's a half-remembered question!
Conclusion: if the user can produce a screenshot or some other reasonably concrete identifying artifact from the game to work with, other than "I kinda remember some stuff about this game I once played.." I have less objections to these questions. I'm still not a fan of them, but I think that's a fair way to limit how many we have.