It has exactly to do with name ordering, since the source of the issue is that the nearest equivalent of the English last name is actually the penultimate rather than final element of the name in the order at issue.
I disagree that this is about ordering. In no ordinary circumstances does that person's name become Peña Nieto Enrique, in that order.
His name uses the Spanish naming system whereby both the mother and father's name are included — like an English double-barrelled name without a hyphen — which is not affected by whether the given or family name(s) come(s) first.
Therefore, the issue is not about ordering, it's about name segmentation and culture-specific name boundaries; the issue is where given names end and family names begin, not what order they're in.
It has exactly to do with name ordering, since the source of the issue is that the nearest equivalent of the English last name is actually the penultimate rather than final element of the name in the order at issue.