Love the '70 and '74 ball, also the evolution from '66 to '70 seems huge.
But I don’t think that difference is actually that big. Sure, there is the color and it’s a icosahedron, but just look at a volleyball. They still look like the ’66 ball looked. So this change of shape didn’t have to happen. (Recent design also abandoned the icosahedron – it’s quickly becoming a thing of the past.)
So how did this design become the synonym for "soccer/football" while the others have not?
I don’t know but those seem like plausible explanations.