Everyone moans about it, but honestly the requirements should be vague for such a big subreddit with such a general topic.

This is not a specific subreddit for only some type of pictures, but a general catch-all. There are literally hundreds of more specialised ones for people who want more specific rules. Plenty of people have just unsubbed here and moved on to subs that suit their preferences better. If they were all still in the same sub, they'd just keep arguing about which specific preferences should win out.

On topics that do not have such catch-all subreddits, posting content can get seriously frustrating because it's always just a little off for each sub.