I'm going to address the major claims of the article.
The author assigns a trait of all characters to Batman specifically, as a negative. Characters cannot exist in a vacuum. A supporting cast is necessary in all but the rarest instances to stimulate character advancement and give the character people to sound of on, so the entire story isn't told in monologue.
This is simply the nature of comics: changes are few, and sudden. You will always get a decade or two of stagnation followed by sudden, sharp advancement. That's just how the business works.
The degree to which batman should be relatable on the superficial level is open for debate. It is important for him to be relatable as representing the internal struggles of humanity--it is less important for us to say "Yeah, he fights crime because his parents died--I relate to that."
This is the best part. What a composite character like Batman is "about" is as much up to the reader as it is to the individual writing him at any given time. The inability of the author to extract meaning from the character says more about him than it does about Batman.
On the most fundamental levels, Batman is about two things: first, human power and independency; and second, the ethical struggle inherent in human existence, which can be boiled down to "do the ends justify the means."
On the first note, Batman has always represented--though not intentionally, I imagine--atheistic sensibilities where other superheroes normally reflect theistic sensibilities. The hero who is given a miraculous gift of power to defend the world reflects the mentality that there will always be someone to watch over us--that God is there to protect us and save us. Superman is a Christ child from the heavens, Wonder Woman was forged by the gods themselves. They represents absolutes: they are morally complete, paragons who come down from the heavens to protect us from evil. They did not need tragedy to shape them, they simply knew what had to be done, and they do it.
Batman, on the other hand, contains a message very different: that there is no one to save us, that God will not protect us, and we will not be supported by divinity or the inherent good of the universe in our struggles. Batman reflects the sensibility that ultimate moral responsibility is on the shoulders of mankind, and we must determine this code and execute it accordingly, because no one else will do it for us. We have to make our own heroes and protect ourselves.
The second point I mentioned follows from this. Batman is frequently the voice of mankind among the superpowered: he is the voice of dissent that insists that superhumanity cannot make decisions for humanity. He insists that the burden of moral decisions should be on mankind. He is not trusting of the superfolk and the authority they seem to think they have. This is the second point: because of this, he represents completely our own struggle to do what we believe is good, and how far we go to achieve these ends, because he does not delegate responsibility to anyone besides humanity. He does not say "What would Superman do" the way some people ask "What would Jesus do?" He doesn't recognize any authority besides humanity when making the decisions that affect us, and accordingly the responsibility to determine what is right or wrong, and the struggles that come with it, all rest squarely on man.
To illustrate this struggle, he represents the pinnacle of humanity: noble, self-sacrificing to the absolute, dedicated, the peak of intelligence, strength, and skill, with an unwavering dedication to what is right and just. At the same time, he represents the absolute bottom of humanity: he is ruled by suffering, dependent on violence, driven at least in part by all of our darker natures: vengeance, hate, anger.
Accordingly, he is constantly at odds with himself and his mission. There is a part of him that is the noble pacifist, who abhors violence and seeks peace through peace, and the part of him that is the vengeful criminal, the part that feels compelled to go out and hurt, to punish, who seeks peace through war. Fundamentally he is our own struggle to find our moral center, our balance. To what degree to we use diplomacy to seek peace, and to what degree do we enforce it?
He also represents the struggle between reason and emotion. Ostensibly, Batman seems to be the ultimate rational thinker: giving no consideration to faith or emotion. But at his core, he is driven by pure, unadulterated emotion with no consideration for reason: his mission, to any rational man, is fruitless, but his emotion refuses to let him leave it be. He cannot rationally justify his rule of non-lethality, it is rooted in emotion, his absolutism and inability to compromise, the childish heart that can't bear to see anyone die. He is at once the ultimate optimist and the ultimate pessimist.
So, in other words, what Batman is "about" is being human. I can't imagine a more relevant theme than this, and it disturbs me that an individual who, ostensibly, has taken time to think on the matter and write this article has not noticed this.
Curious--this sounds like what he did in Batman Begins.
Reality, no--psychology, yes. Every villain should reflect a fundamentally different philosophy on being human, and accordingly psychology is critical. The villains are meant to be the men that Batman could have (or could still) become. The Joker is the man that accepted violence as the truth of the universe, where Batman is the man who absolutely refused it. Two-Face is the man who could not reconcile that conflict, and split himself in two for it. Scarecrow is Batman's dark emotion, Freeze is his cold caculation. I said that Batman is mankind's struggle to find his moral center, the blanace between good, evil, emotion, logic, and each of these villains represents what Batman would become were he not balanced, each is an extreme version of one of these elements oh human life.
Because they are meant to represent extreme, they do not need to be realistic. They can be incredible, impossible, fantastic borderline supernatural things, but the core will always be there, and that is their root in humanity.
This is one of the few sentiments in the article that make sense. Certainly there are a myriad of possibilities--not to take anything away from the realistic approach, but many are extremely intriguing and I want to see them in future films.