I thought the Aly Bain and Phil Cunningham sessions were a rare example of good TV showcasing of roots music. However, I daresay it was again largely Celtic and American music, with little English folk music being covered. BBC4 does have some great music documentaries, but English folk music is very rarely covered.
The problem is that English folk has a serious image problem to rise above, and TV companies can rarely portray it without reverting to banal stereotyping (bales of hay, etc), or ensuring that a presenter talks over any such performance (eg pub musicians forever consigned to the backdrop).