But A0283 surely any root cause(s), if there are multiple causes for this particular accident, had to be before the departure. The fuel calculation, the decision to depart with that fuel load and flight plan without a fuel stop, all these are the root cause.
Perhaps there could be other causes that influenced that decision, eg commercial pressures, some misguided belief that the plane used less fuel than the book said (hypothetical speculation here), etc. But anything that happened after they pushed the throttles forward on departure is just reaction not cause.
Sure they might have been able to get recover, get away with it, save the day with some skilled cool headed flying. Then it would have been a near accident caused by the fuel decision. That decision was still the cause.
The improper handling of the fuel emergency (by the pilots) was not great. But the previous aircraft getting priority did not cause the accident. ATC did not cause it. Those two didn't even contribute. Maybe it was unlucky that that airplane was there. But flying isn't supposed to depend on luck.