I don't dispute their skills, nor can I complain at the atmosphere in the towns where I attended those festivals - I had a great time, but they simply weren't what I was expecting and, not really what I wanted.
There were no English groups at any of the festivals I saw.
As always I can only speak of the ones I saw - they obviously won't all be the same - I believe there are a couple (a few) up in Brittany which come nearer to what I see at British festivals.
Like the blues festival in Cognac - the atmosphere in town is magic and they are a great bunch of people, but I'd be happier with a different kind of music! :-)