I cringe when I hear the novice say “All the Irish records were destroyed.” They simply were not. In the 1922 Irish Civil War, the Public Record Office in Dublin was burned. As tragic as that was, the primary records destroyed were; half the Church of Ireland registers, censuses through 1851, and most pre-1858 wills. The informative 1841 and 1851 censuses were probably the most terrible loss.
Keep in mind most people never left wills and only about 12% of the population was Anglican, so the destruction of these records didn’t affect the entire population. My advice is to educate yourself as to what the 1922 fire meant for your particular ancestors.
Where I think the novice gets rightly frustrated is that most Irish records were not kept in the sense records were in other parts of Europe. The average Roman Catholic and Presbyterian register begins in the late 1820s or early 1830s. Poverty and the landlord-tenant relationship kept most people out of the Registry of Deeds. The popular Methodist Church did not come out of the Church of Ireland and Presbyterian churches until 1818.
Now the other side of the story is that many records were not deposited as of 1922. Overnight second copies of some records, private genealogical collections, tax records, Masonic records and published data from pre-1922 books became the prime sources for Irish research. Most of these are now on microfilm at the Family History Library in Salt Lake City or repositories in Ireland and Northern Ireland.