I've seen this screenshot doing the rounds but the Irish Dept. of Foreign Affairs has confirmed they've seen no evidence of a breach. Not sure how common it is but perhaps just a bluff to get some Bitcoin?
That would still constitue a breach. Demonstrating a breach means showing info they should absolutley not have access to.
That said such Irish systems are very imperfect e.g. low wages for IT staff and there was breach/attack of the countries hospitals systems during Covid however the gov acknowledged the attach at the time. So very much possible.
I'd need to see more evidence before I'd take this claim seriously though.
But it's easily a breach that you don't notice. Does the organization track every time a file is copied, moved, or transmitted? How many lost thumb drives are there? Laptops with sensitive data have turned up on auctions sites before: https://www.nytimes.com/2020/03/17/world/europe/germany-miss...