I mean, the movie isn't about the broad topic of the nuclear arms race, it explicitly makes the choice not to show the bombing of Japan, there are many things it consciously leaves out. It's not a documentary, it's explicitly very subjective.
Yes, the movie is subjective and a biography. It also seems to be interested in the necessities for the development of the bomb. What humans needed to contribute and how they saw the moral implications of the weapon, as well as what efforts were needed to realize the bomb.
The article opens with a very memorable and important scene in the movie.
Then it connects this to the realities of uranium mining.
Which are relevant until today.
Why is this not an omission? Is the movie not a document of zeitgeist itself, does it not meam to evoke any thoughts or questions?
It does not need to be a documentary to be omitting something, especially because Oppenheimer's biography has moral and political aspects that the movie seems interested in.
I don't read the headline of the article as some kind of accusation against the movie. The headline is supposed to spike interest in facts that many people don't seem to know or care about, despite having opinions on them.
Crucially, the title is actually fairly thoughtfully worded (for once). "didn't show", not "failed" or "neglected to".