People have said this for decades, and i've come to realize how much I disagree. This argument is most likely based on his lack of superpowers. True, he has the physical limitations of an ordinary man, trained to the peak by hard work and discipline. BUt I'm afraid his realism pretty much ends there.
First off, let's look at the fact that he's a multi-billionaire. I know that such people exist, but I am not one of them nor is anyone with whom I'm personally acquainted. I doubt many comic fans can say otherwise. So this aspect makes him an intangible, unrelatable character in a sense. Then you look at his history: Parents are gunned down in an alley by a desperate mugger, who in turn leaves a living witness? Pretty unlikely. Then he's raised by Alfred. How the hell does the custody of the sole heir to a massive empire fall into the hands of the help? And how do you parent your boss? "You're grounded!" "You're fired!"
Then there's his tech; I won't talk about the vehicles other than to point out they're aerodynamically unsound. I SERIOUSLY
doubt that a Batwing would fly, or that a Batmobile would pick up much speed. (Keaton's was said to actually be slower than a Honda Civic.)
The Batarang is another one. Boomerangs are designed a specific way, which enables them to fly in an arc and come back.
If you tamper with that design, altering its basic shape-making it look like a bat, for example,
IT WILL NOT WORK. Nevermind adding to its weight with the toys that he comes up with or attaching a line.
Then there's the glider cape; cool as it looks-can't be done. Closest thing they've got is those suits we saw in Transformers 3. Grapple guns have yet to be shrunk down to where you can carry one in your pocket. I could go on and on. Batman's tech is beautiful but we're years away from seeing that stuff in the real world. I honestly think he's the reason some ot fhat stuff has progressed as much as it has; science chasing science fiction.
Then there's his enemies: THis
is probably the LEAST likely result of facial scarring and a chemical bath. This guy
could probably survive his disfigurement but good luck understanding a word he says.
just doesn't happen. Same goes for Ivy, Bane, Croc, Man-Bat...
I'm not saying this because I have a problem with Batman in any way. I love the character and I've enjoyed him for years. I can PROMISE you I will have my butt in a theater SOMEWHERE when the next movie opens, probably wearing a Batman t-shirt. It's just that the truth is, he's no more grounded in reality than a guy getting bitten by a radioactive spider.