Indigo_Dingo said:
But the DC universe actually is. If you were to take down the number of superpowered individuals (you have to consider the villains as well) in the Dc universe, the list would be damn big.
That's a list of all characters (superhero, villain, and otherwise) across all the DC 'universes' from every time span in every location. In 'reality', you'd only see a handful of heroes and villains in any single location at any given time, outside of incredibly rare events. DC has very powerful characters, but a generally low superhero density compared to Marvel.
An MMO will have as many superheroes as DC has ever had all in one area, with hundred or thousands active 24/7. It's a little bit more complicated to make 'work' in an established fiction.