i never said there is an anti-cork approach.. but i do feel there is a pro-dublin feel. possibly not so much in recent years but definately in the past. i am fully aware that there are more people playing football in dublin but i have seen it myself when i was involved with underage teams in the past. it was also more of a laziness issue where managers/coaches/scouts wouldn't bother going to sligo to see a local team play a team from mayo in the FAI U15 cup for example. however they would go to the winner of that game if they played a dublin team in the next round.
i cant comment on the other non-dublin players you listed above but i happen to know that the Mervue Utd player listed played on the mervue team which defeated crumlin utd in last years u14 FAI cup final. the crumlin team had 6/7 players involved with the irish team at the time and mervue had none. just an example. also there are still countless young players nationwide who play for DDSL teams in order to achieve international recognition.