Thanks for the info. I knew that Kiran Rao was assistant director but Ayan was not on my radar.
I looked him up and saw that he was also credited as one of the screenplay writers of Swades.
I knew that he was assistant director in KANK and that he was rather close to Karan who produced Wake up Sid and YJHD.
Btw, I'm convinced that the story Ayan presented to Karan in 2014 wasn't at all the story we now got in Brahmastra. I don't think that he had such a (bland) love story in mind but had to do the first of many changes to follow Alia's (Karan's) wish to cast Alia as Ranbir's love interest. I even imagine that he was mighty annoyed to have her fangirling during the shoots (and I think the same about Ranbir).
Why did it take soooooo long to shoot this movie (Covid is just an excuse for one year)? So long that a perceptible lack of enthusiasm shines through the movie. I guess: many changes in the script, Karan adjusting to certain modifications in the Indian filmscenery (i.e. Rajamouli's worldwide success with BB2, Hindutva with its growing Islamophobia) and to other producers, tensions on the set and in the relationship between Ayan, Ranbir and Alia, and Ayan now doing a movie that wasn't anymore the movie he initially wanted to make.
I read that Ranbir didn't take money for the work he did (rightly so...). Apparently he even supported the making with his own money (he is credited as producer on imdb).
Another producer is the prolific company who made the VFX work (DNEG, which isn't an Indian company although they have 3 working locations in India - War was the first Indian movie in whose VFX-work it was involved, if I'm right...and they also did 83, RRR and the Harry Potter movies' VFX).

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