The Regulator seems to be just assessing the short-term commercial interests of EI and FR. This is a good political intervention, the kind that rarely happens.
I don't understand your logic. Abolition of airport duty = FR introduces more flights/pax, EI to a lesser extent. If the duty is replaced by punitive DAA charges then FR/EI = fewer flights/pax. FR will be seriously
off having kept their side of the bargain. They should have known better than to trust any politicians and, in particular, the current lot who have reneged on more promises than the 10 previous administrations.