Bear with me, because I still can't do Blue Clickie links. But I can submits URLs in a post.

It occurs to me that some readers, who know even less than I did when I wrote the original post, might want examples of the "cabaret harp" being scrutinized here.

Both these pages describe the same recording product.

https://siopa.gael-linn.ie and search for "Amhrain Ghra."

http://claddaghrecords.com/index.php/amhrain-ghra-songs-of-love-by-irish-female-vocalists.html

Multiple singers/harp-accompanists here, including:
Máire Ní Scolaí
Eilidh Ní Marchaigh
Fionnuala Mac Lochlainn
Marjorie Courtney
Deirdre Ní Fhlóinn
Kathleen Watkins
Gráinne Yeats
Mary O'Hara

Seventeen titles, they all appear to be Irish/Gaelic, including "Róisín Dubh."

No, I have not heard any of these records myself.