Yoru's entire objective from the beginning was to get Chainsaw Man to vomit up nuclear weapons, but somehow forgot along the way and only became interested in turning Denji/Chainsaw Man into a weapon.
She forgot because everyone eventually forgets about the stuff Chainsawman eats. It takes longer for strong devils to forget, but even Makima forgot the original name of the hybrids for instance.
Since nuclear weapons have somehow made a return, and looking at Denji now, does this mean everything Chainsaw Man has eaten has now been freed?
My guess is no. I think the stuff Chainsawman ate always have a chance of returning as time passes (they mentioned somewhere that all the concepts he ate will eventually return) and Denji being temporarily dead opened a window for nukes to return.
