'Gritty reboot'; the phrase has managed to become a cliché in a remarkably short time. In essence it means taking some well known tale that's generally told with clear black and white definitions of who the bad guys and good guys are and adding shades of grey to blur the moral lines; making the fictional universe more realistic
Now in theory this can be a good thing. A problem that is prone to be pop up in fiction is that anyone whose good at their job can't really be one of the bad guys; doubly so if they happen to have a sense of humour. What this means is that these 'bad guys' are really good guys forced to serve the forces of evil by some outside factor. Some authors can't seem to cope with the idea that someone could be smart, charismatic, and charming; a person who is the the life and soul of the party one night and then gets up bright and early to order the execution of thousands. So yes the theory is good but the practice is all too often abysmal
The reason for this seems to be that writers seem to assume that 'gritty' and 'realistic' means 'lets make everyone a mean, despicable...well lets say 'jerk' to keep this blog family friendly. I personally think this is every bit as unrealistic as the idea of square jawed heroes and moustache twirling villains. Instead of clear black and white these 'gritty' stories often reduce everything to the same tone of muddy grey. Far from adding nuance and detail they simply obliterate it.
History shows that people are seldom all good or bad; business men who ruthlessly crush all competition and make a fortune only to turn around and spend that one on philanthropy and charitable works. Conversely there is the good neighbour who is warm, friendly, always happy to lend a hand; and just happens to wear a hood and burn crosses on the weekend. People are complicated and its no more realistic to portray them all as devils than it is to have them all be saints.