In skeuomorphism you design concepts to resemble real world objects. People associate your designed concept with the real-world object and act as they would towards the object.
We name ‘off-topic’ areas of the site the water cooler, the cafe, and the break room. There is nothing wrong with this, it can form useful associations.
Skeuomorphism can be useful if we use it well*. The problem it isn’t.
Is the ‘water cooler’ (colleagues spending a few minutes in a corporate environment gossiping about their boss) really the best real-world object we can think of to stimulate the type of behavior we want? We can do better.
Think of the places where you have the most fun, exciting, and engaging interactions (don’t default to a pub/bar). Name this part of the community after that area.
This works for the places where you want people to share their very best ideas, give each other deep emotional support, and put ideas into practice. Think of the real-life contexts where this best happens and name your objects after these.
*the opposite, perhaps, is ‘flat design’ where the object has no meaning. You make up a word or symbol and use it