Big daddy Nolan sold Dunkirk for 500+ $mln WW and almost 240 $mln in USA alone, if we will count the inflation factor. So, Barbienheimer and IMAX just a tasty cherry on a top of big cake. I don't think if Oppy had made 600-700 $mln WW, someone has been upset.
I meant Barbie opened there month ago and Oppy just last Wednesdatly, with this time gap, and the whole idea of Barbienheimer to watch both movies back to back.
So, I think the Barbienheimer obviosly helped both pictures, but Barbie and Oppy would be successful anyway, just a little bit lesser, may be.
Again, all of that, just my humble opinion.