Okay, let's try this a different way.
What does .500 represent? It is a statistical representation of a completely "middle of the road" team at any moment in the season, a team that wins some games, and loses the exact same amount of games. Record could be 2-2 or 500-500. It all means the same. Whatever opportunity that team has had to distinguish itself as a good or bad team, they've taken that opportunity and... results are statistically inconclusive.
So when you say, "X wins over .500", it actually means "X more wins than if we were a completely middle of the road team".
Now we all know .500 is NOT a middle of the road team in the NHL, it's actually quite bad. I want to stress that .500 is just an arbitrary marker. It's only significant because our puny humanoid brains need simple, pure concepts to understand the world, so we pick simple numbers to relate things to. So we use .500 because... Well what's more simple and pure than that? You win some, you lose some.