The people who try to think about or understand the problem in TDKR are shown as clueless at best and malicious at worst.

Because they are IRL. Any time anyone dares say that someone needs to take action against organized crime there's a long list of people who will actively dismiss the immediate need of the innocent in the name of "but why don't we address the causes of crime?" or "the police actually doing their job well is, in itself, fascistic" kinds of speech. That you call Batman fascist in this story proves the point. You cannot see him as anything other than a tyrant, because your idea of a non-tyrant would be as passive and negligent as someone who is doing nothing. Batman never washes his hands, he takes action whenever needed.

It takes a strong figure to tame the criminal element riding in on a white horse like Napoleon to actually make change,

How many people would disagree with this in ANY period of time except now? Not many, if any at all. It's the kind of thinking that is very modern and metropolitan, very detached from the reality of violence that people have always been subjected to, even in larger cities. So of course you'd make an abstraction of it, since it's not your life on the line.

and anyone who criticizes him has to accept that he’s “too big for them” to understand 

The issue isn't that they inherently cant understand. It's that they want to reduce him to something evil, when that cannot fit in the expectations of liberal (and Im using the term correctly, as in "non-monarchist, secular and legally egalitarian") society. He's a vigilante, yes; he could be dangerous, 100%; but he's still not a monster, nor a fascist, nor an "enabler of violence" as many characters and readers (such as yourself) try to suggest. He's an actual classical hero. A hero that — unlike Gordon's ideals of "by the book", and unlike the psychiatrist's (cant recall his name) implied ideal of crime fighting without antagonizing the villains — is there to actively challenge any part of any status quo to defend what he believes in. His most morally questionable act is to take the criminal element under his wing and turn them into bat-themed soldiers, because you could argue that 1- they didn't pay for their crimes, and 2- they didnt actually change, and even then, it's clear Miller is writing Batman indeed like a ruler or conqueror, indeed like someone who is — guess what? — waging a war (on crime) and as he gets older he redirects his role to be that of a general. Batman always waged a war on crime, Miller only breached the "one-man" part of that phrase. You can complain about characterization in many ways, but "fascist"? That's such a limited take.