There's a reason why batman is a fictional character and not some guy in real life.
In fiction, one doesn't have to worry about legal repercussions or the aftermath of their actions, whereas in real life, things are way.... more different. You can easily find some skits that poke fun of how unrealistic these fiction pieces are.
Now, while Karakura is technically fictional, it has to account for realism more than your average comic or show, given how everyone is a writer in roleplay. Its nature will inevitably cause issues among writers, which doesn't tend to happen as often in other fictional media.
As a matter of fact, I remember some people trying to act as heroes, but all it did was cause issues with them not FearRPing officers and getting in trouble with staff over wanting to stand out and be the main character over others (Yes, your character is the main character in your roleplay environment, but in this case I'm speaking from a global standpoint)
To sum up, batman does go hard, but it's not something that'd work in practice