It’s a big deal because with no layers if you go to a spot, you know only you exist in that place on your entire server. It adds a sense of realism. With layers, nothing matters because anyone could be doing the same thing as you at the same time. It’s difficult to find pvp when you hardly see anyone. In addition, the world feels way less alive when i look around stormwind and it’s not packed.
Imagine if were in shattrah and there’s just no one there? It will be so lame. Blizzard created this problem and players accepted it because blizzard trained them to accept it like dogs. 2007 blizzard would never have let this happen.