The Mods have discussed this. If and when we feel like memes or gifs or whatever, in a specific thread, are out of hand we’ll deal with it. Pic/gif responses are a commentary on the thread, or what’s said in other comments, just like those that only have words. Does it get a little wild sometimes, sure, but we’re not going to institute a new rule about it as this is covered elsewhere in the rules.
As always, if you feel a specific comment is wildly off topic or inappropriate you can report it and we’ll deal with them as they come.
Note: There is flexibility in how we deal with off topic issues as demanding strict obedience to topic is simply unrealistic.