It's good to compare the Wang and Argerich performances.
The opening declamatory section already sets out the major differences between the two interpretations - Wang has more power and Argerich's tempo is slower and more reflective; I'd argue that both are equally valid, with the former emphasising the romantic view of naive innocence crushed by reality, and the latter the melancholia or ennui that comes with experience. It's an interpretative choice that anyone playing this piece will need to address, and the key thing (imho) is how this plays out later, particularly in the solo piano section (around 6'30", or 7"). What I think I hear is Argerich repeating the approach she has taken in the opening section - slow tempi, very reflective, whereas Wang takes a different approach which is consistent with how she chose to approach the opening section. Again, I think both are equally valid, but I think Wang finds more light and shade in the connections between the different sections, and the movement in thought and time as the piece progresses - Argerich sticks to the approach she takes at the start, and there is less progression in this. The major difference that I can hear is in the quality of orchestra and conducting - Barenboim has the edge here, without doubt (the clarinet solo after the opening section makes that very clear!). Overall, I'd argue that any difference between the two pianists is one of interpretation, not of capability or 'greatness' (whatever that is).
I was listening to several performances of Brahms op.76 yesterday when I began to read this thread, and I'd certainly like to hear Yuja Wang's interpretation of those eight pieces.