The entry requirements for admission to courses in higher education institutions are determined by the institutions themselves which are legally autonomous and academically independent. I have no function therefore in setting admissions criteria.
I understand that the National University of Ireland generally requires applicants, who were born and who had all their education in the Republic of Ireland, to present a Grade D in Irish at Ordinary Level in the Leaving Certificate for entry to courses in its constituent universities (UCC, UCD, NUIG and NUIM) and its recognised colleges. The University of Limerick also has such a requirement. Applicants to Dublin City University and the Institutes of Technology generally require a Grade D at Ordinary Level in either English or Irish to meet minimum entry requirements.
The Colleges of Education, the teacher training colleges, require a Grade C at Higher Level in Irish.