You southerners fail to realise that there is a world of Northern Ireland outside of Belfast..
There are areas where Dublin will never be a convenient airport of choice.
Yawn. Dubliners certainly realise a reluctance to add up figures by people who live West of a line drawn through Mullingar.
A few salient facts:
Dublin Airport passenger numbers 21 million
Belfast International passenger numbers 4 million
Belfast City passenger numbers 2.5 million
Cork Airport 2 million
Shannon Airport 1.6 million
Knock Airport 700,000
City of Derry Airport 400,000
Farranfore Airport 300,000
I'm probably leaving out somewhere, but that won't greatly impact the figures.
There's about 25 million passenger journeys in and out of airports in the Republic. Over 80% of them are through Dublin Airport.
There's about 32 million journeys in and out of airports in the whole of Ireland, if we add in the 7 million relating to Northern Ireland. Dublin Airport accounts for 65% of all island traffic. I'd suggest that means Dublin is already, overwhelmingly, the airport of choice for most people in Ireland.