Because he doesn't make mainstream films. He tried it with Manmarziyaan and it didn't work. It wasn't good either.
His best works are DevD, No Smoking, Ugly, and GoW. None of those movies have massy elements. You could say DevD does, which is why it's the only commercial success of Anurag's career.
He's the antithesis of Rohit Shetty/Karan Johar. Just like Rohit's obsession with shitty cinema and KJo's obsession with weepy melodrama, Kashyap is obsessed with character study of highly flawed people. His characters are flawed. They are twisted. They show the darker, uglier side of human behavior.
Usually, masses avoid such flicks as there's nothing for them. He makes movies for cinephilies and critics.
Is he a genius? No, he isn't. He's an utterly mediocre filmmakers in his own words but he's a genius within that mediocrity. He's amongst the top-5 filmmakers in Hindi cinema today.
I'm not fond of his recent works. But there's no denying that he's the king of independent cinema and an inspiration for all filmmakers.
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