I think they mean just for the records they have.
Although I did some parish registers in Wicklow and one of the births I was able to get from the registers is not on roots when the records became available on line.
Roots only put on what is given them by their local genealogy office member. When I asked them if they wanted the persons details that weren't in their records they told me to contact the Wicklow office.
I did but they never answered. I do know they collected the local parish registers and transcribed the information themselves before joining roots. I was in the office for an appointment with the Archivist and she had just returned from the Church. Errors are made I guess as we are all human, but this is so important. One of the reasons there are so many errors in the Latter Day Saints materials is that 'students' did the copying of the parish records from
the National Library.
The Earl Fitzwilliam built Catholic Churches and schools on his lands before 1829 as well as Protestant. I think he was the Member of Parliament from the area as well as the Deputy Lieutenant Governer for Ireland. Or some such position. He came into
disfavour as he was in favour of returning of land to the irish.