In this dark DC future there were no ideal heroes around to motivate and inspire people to rise above their own selfish needs. Even with Superman around (although working in a clandestine fashion). The heroes bowed out, and the standards of quality of life and moral code represented better by the Flash, the Green Lantern and Diana went down the toilet.
Except IIRC we never find out WHY. Batman giving up is his choice (presumably after Jason's fate, and even that was left vague in DKR) and Superman went "politically hamstrung". Where were all the OTHER heroes in this? Wonder Woman, the Titans, the JSA and the like?
It was when the news reporters mentioned that the cities of the United States were in chaos in the nuclear winter, there was ONE city where people could walk safely down the streets. Where the rebelling youth of our future were guided out of the gutter and darkness by one man.
I'm a Batman fan, I'm a BIG Batman fan, he's one man in one city, that works, but to suggest that he's the ONLY man, in ANY city, is just not impressive storytelling.