Remember, we are in the Ryanair thread right now. Just try to enter a simple Finnish name like Äijö or Hämäläinen to FR booking system. Even worse, try Polish or Czech names with their ś ć ż ź ł š č and so on. The system probably won't accept them. So, what are we talking about here.
We don't refer to Germany as Deutschland, Hungary as Magyar or Finland as Sumoi and so on; because the thread is in English. So why refer to Ireland as Eire, which isn't even the correct spelling. Éire is the official name of the country in Irish and Ireland is the official name in English.