I think there's a simple policy we can enact when it comes to questions asking us to identify multiple items has to come from one single game artifact. Not a wall covered in characters, not someone's idea of a test, not a game "competition", only an artifact from the game itself. As an example, take a game's manual cover or boxart. While definitely the epitome of no research, here's a pretty reasonable expection there that all of them are related, and come from the same source, and therefore is a much more focused area of expertise. Depth of expertise comes to the fore.
The few times we've had people ask about multiple items, they've been heavily downvoted, as they're presented with no context, no explanation, and they're generally just competitions or brain teasers, often providing tiny, hard to source snippets to confuse participants.
These questions generally lead to incomplete answers, invariably where someone can recognize some of the artifacts, but not all of them. Not to put too fine a point on it, but answers are supposed to answer the question. Not identifying all the artifacts means you're not answering the question. Answers are supposed to be standalone; each one should fully answer and solve the problem presented.
We have a tendency to gather incomplete answers in drips and drabs, and then someone comes along and posts a fully complete answer, pulling from all the other answers. That's not expertise. That's amalgamating list answers into a bigger list.
Back to a consistent policy: Multiple item identification should be held to a stricter standard, one that brings our expertise to the fore. I propose that standard is an actual artifact from the game in question, such as boxart or a manual cover. No related artifacts, such as this T-shirt question, or brain teasers, or competitions. They can then be easily answered by a single person, without need of interpreting an artist's redention of a character, community wiki, or risking incomplete answers.
I think there's an argument to be made for multi-game series, such as Zelda, Mass Effect, Final Fantasy, what have you, but for the sake of simplicity, I say we limit it to a single game.
Unless the artifact is from the game, at most the question can ask is to identify a single item.
Broading of quantity leads to a narrower list of acceptable artifacts, while lessening the requirements for identification expands the artifacts to non-game items. No lists, no competition, and best of all, no incomplete answers.