Is this a general policy of Aer Lingus not to accept European travellers with ID cards into Ireland?
Aer Lingus policy for travel within the EU is:
(There are slightly different provisions for "To and from Britain" but these appear to cover only between UK and Ireland for those born in Ireland or the U.K. and also a citizen of either country.)
/ 26JAN17 / 2345 UTC
National Sweden (SE) Destination Ireland (Rep.) (IE)
Ireland (Rep.) (IE)
Passport required.
Passports and other documents accepted for entry must be valid for the period of intended stay.
Passports issued to nationals of Sweden must be valid on arrival. Passport Exemptions:
Nationals of Sweden with a national ID card.
Passengers with an emergency or a temporary passport.
Visa required, except for Nationals of Sweden.
Minors:
Children up to/incl. 16 years of age For details, click here
WARNING! In accordance with European Union (EU) Legislation, all minors who are nationals of Sweden will be expected to hold their own passport or National ID Card (where applicable) when departing from Bulgaria, Croatia, Cyprus, Romania or a Schengen Member State For details, click here.
A separate visa is required for children up to/incl. 16 years of age if For details, click here Additional Information:
Visitors holding passports containing a British inadmissible stamp could be refused entry. Warning:
Immigration controls apply for visitors arriving from Great Britain and Northern Ireland, For details, click here
Timaticweb Version 1.3 26 January 2017
Freedom of movement; ID card valid