Notable people with the name include:
Oilibhéar Báicéir (born 1974), Irish hurler
Oilibhéar Brádaigh, Irish Gaelic footballer
Oilibhéar Breathnach (born 1992), Irish hurler
Oilibhéar Breathnach (1937-2016), Irish hurler
Oilibhéar Cainín (born 1976), Irish hurler
Olibhéar Coileáin (born 1972), Irish hurler
Oilibhéar Conchúir (born 1975), Irish hurler
Oilibhéar Criú (1947-2020), Irish Gaelic footballer
Oilibhéar Crionagáin (born 1947), Irish Gaelic footballer
Oilibhéar Croiligh (1940-2025), Irish scholar and priest
Oilibhéar Fathaigh (born 1975), Irish hurler
Oilibhéar Mac Giolla Mhuire (1947-2025), Irish Gaelic footballer
Oilibhéar Mag Eochaidh (1935-2020), Irish hurler
Oilibhéar Mac Seanlaoich (born 1943), Irish Gaelic footballer
Olibhéar Mac Craith (born 1938), Irish hurler
Olibhéar Moráin (born 1975), Irish hurler
Oilibhéar Murchú, Irish Gaelic footballer
Oilibhéar Pluincéid (1629-1681), Irish Archbishop, Martyr and Saint and one of the greatest Irishmen to have ever lived
Oilibhéar Raghallaigh (1936-2009), Irish Gaelic footballer
Plenty of Irish people have the name...look up them on Google or Linkedin and see for yourself.
If someone with French heritage were posting here about giving their child the name Olivier would all the commenters have been calling it "pretentious" or that it is simply a French version of Oliver so pointless.
As an aside calling it pretentious is hilarious to those in the know as the Irish are typically the complete opposite of pretentious as Irish culture values humility and egalitarianism...which is part of the reason they are liked around the world (apart from Little Ingerland bigots)
Or is it the brexiteers saw the Irish origins of the name in the post and the anti-Irish knives came out in a way that wouldn't with a French person talking about Olivier? By the way anyone from around the world can use whatever Irish name they want.