The true reason Abhishek Bachchan isn't in Bunty aur Babli 2 or even Dhoom 4 is because

Bunty aur Babli 2, which stars Rani Mukerji, Saif Ali Khan, Siddhant Chaturvedi, and Sharvari Wagh, has received a lot of attention from film enthusiasts. Rani Mukerji will reprise her role as Babli from the first instalment, while Saif Ali Khan will play a new Bunty. He has taken over the role of Bunty from Abhishek Bachchan. Fans were left perplexed after seeing the trailer and questioning why Abhishek Bachchan did not repeat his role. As a result, the explanation has now been exposed.

During the filming of Dhoom 3, Aditya Chopra and actor Abhishek Bachchan had a professional feud. Yes, you read that correctly. Abhishek Bachchan, who had a strong relationship with Aditya Chopra a few years ago, is unlikely to appear in any more Yash Raj films.

Dhoom 3's script was continuously being tweaked in Aamir Khan's favour. Abhishek's protestations to director Vijay Krishna Acharya and producer Aditya Chopra went unheeded. The climax was the final straw. When Abhishek arrived at the shooting location, he was informed that the entire climax had been changed without his permission. This is when Abhishek took a stand. He informed Adi that he would not be returning to the Dhoom franchise.

Producer Aditya Chopra was not pleased with Abhishek's decision to speak out against it. Souce goes on to state that Abhishek and Aditya Chopra have been at odds since that incident. Abhishek Bachchan was given Bunty and Babli 2, but he refused to work with Aditya Chopra again.

Abhishek Bachchan plays a pivotal role in the Dhoom franchise. Part 4 was expected to start soon, however, it appears as it will never happen. Dhoom 4 would not be the same without Abhishek Bachchan.