And indeed many field recordings of traditional singers and musicians are well blocked from non-academics accessing them such as the Howson's collection of traditionl English singers.
"John Howson English, Irish & Scottish Folk Music Collection
Number of items in collection: 4382
Recordings in this collection are available for Higher and Further Education institutions only."
But see here how they have a different attitude in the US. The field recordings made by Alan Lomax and Seamus Ennis in Southern Irelend from 1951-53 are freely available to all.
Many of these recordings featured in the BBC's Irish Radio Ballad 'Stone of Tory' (which was only aired but once).
"Stone of Tory, 1950. A full-scale ballad opera, broadcast from Dublin, featuring Irish rural singers and a cast from the Abbey Theatre."