The thing with Anurag Kashyap movies is:

• There are no overacting or over-the-top action scenes. There is deliberate underacting at times :)
• People in his movies talk with regional accent and slang. No one talks in his movies talks in sankretized Hindi for the Fuck of it. The heroin in one of his movies says "permesson" when she meant permission. That helps with the immersion a lot. I have never been to Jharkhand or Bihar but after watching Gangs of Wasseypur I felt like I have visited both of those places :)
• His characters just like his movies lack sophistication and finesse. He doesn't employ rich movie stars who can't act humble. He picks struggling actors or unknown actors or underdogs for his movies.
• His movies are realistic. The situations in his movies are not out of the world David vs Goliath type of situations. His protagonists & villains are not superheroes. They routinely do dumb shit all the time, just like normal everyday citizens :)

One of the heroines in his movies begs Infront of a movie theater not for food or money, but for a movie ticket :) if you think about it, poor people want to watch movies just as much as they want food and material comforts :) there are those kinds of subtleties in his movies that make them relatable. You can relate to the characters in his movies.

• Absolutely 0 melodrama. No kidney-touching dialogues.
• His characters don't recite dialogues like they have practiced those dialogues 100 times before the shoot. There is a bit of hesitation when they talk. Because let's be honest when we talk, we don't talk like we have rehearsed what we are going to say 100 times. We are framing what we are going to say in our head while we are talking. These little things really help with immersion a lot.
• He shows how common people would react in specific situations. He doesn't show an overly idealized society where people have lofty ideals and stuff and they always do the right thing. His movies don't preach. His movies don't have a message.
• He doesn't hide the ugliness in society for the sake of cinema. Whether it is the dirty on the street, corruption, immorality of certain people, or lack of ethics. His movies are raw and unfiltered.
• You can compare his movies to street food, while other directors like Sanjay Leela Bhansali's movies are a fine dining experience.
• His movies are almost bereft of songs. But all his movies have this one dude who sings some weird songs in a horrible way. I don't know if he has used a real song for this in any of his movies. It's almost funny how bad he sings those songs but the lyrics of the song have an actual deep connection to the story.
• At the end of his movie, you leave with a deeper understanding of how Indian society works. You understand why the people you meet on an everyday basis behave the way they behave :)

Also here's an interesting incident that happened to Anurag Kashyap to illustrate his mindset better.

He was originally supposed to be the Director of Tere Naam. He was not convinced that Salman Khan was the best choice for the movie. The hero was supposed to be a person from UP's Agra/Mathura region. He asked Salman to grow chest hair to make him seem like an authentic UP native. For this, the producer called Anurag called him to his house and threw a glass bottle at him. And removed him from the film 😂