Here is the point that really needs to be emphasized though. Gretzky was a pass first, pass second, pass third then shoot kind of guy. OV has always been a shot first, shoot second, shoot third player. Moreover, Gretzky like McDavid was primarily responsible for the key plays leading up to his goals. OV has often depended on a playmaker to score.
In the end I suspect that OV will be recognized as the greatest goal scorer of all time. But I suspect that had Gretzky been nearly as goal focused as Ov, Ov would need another 5-8 years at least to catch him.