Jim I hear what you are saying but I am afraid we will just have to differ in our interpretation of what folk is.
1)My simple test would be that it encompasses the range of material    encountered in a successful folkclub.
2)The modern world has swallowed the traditional sources of folk in the western world. There are no hoary handed sons of the soil left-they drive around in air conditioned tractors with the radio blaring full blast.They do not have time to sit under a hedge, chewing a bit of grass while composing folksongs. The travellers may have some remnant of the old ways of generating and transmitting an oral tradition, but the modern world is shrinking their numbers daily.
3)To finda genuine folk tradition you would have to go beyond the confines of the modern world and there are not too many places left.
Maybe in parts of Namibia or the Gibson desert you might find traditional lifestyles, but even there the modern world has encroached.
3)The academic definition of folk renders the genre to be an anachronism and now fossilised. I do not accept this and I am sure many others do not.
4)To accept your rigid definition would immediately wipe out a complete body of Irish Ballads as typified by songs by Pete St. John
5)If you accept folk is a living, constantly evolving and expanding entity then modern works have to be included. No matter how peripheral the lyrics may be to the human experience, if they encompaass any part of it I would argue it is folk.
If you insist on a strict academic definition of a genre that has no modern contributors you have sentenced it to death.