Those races were sailed in a different wind range where ETNZ has less of an advantage, if any, compared with the other boats. They designed a weapon in the 8-12kt breeze range.
I thought so too, so I went and checked. Wind for QRR 2 R 12 was 9.7 Knots. Wind for AC R4 was 10.3 knots. So, QRR 2R 12 was within their weapon range during the qualifiers.