Folk song was created by the people - 'folk' - pretty well defined in numerous works listed elsewhere and accepted universally since the term came into use in the first half of the 19th century.
Nowhere has it been suggested that the 'folk' are unable to create their own songs and music, but that, thanks to the development of and accessibilty to technology, they no longer do so. They/we have become passive recipients of, rather than participants in our culture.
There is ample evidence to prove that communities in area such as the West of Ireland, the North east of Scotland, East Anglia, Travellers, fishing communities....... at one time not only took up songs from the outside and adapted them to suit their own particular circumstances, but also made new ones to serve the same purpose.      
                        
                                                 THEY NO LONGER DO SO.

The Irish and Scots Travellers were probably the last to cling on to their culture, thanks to their relative isolation, but this disappeared virtually overnight with the advent of the portable television and the social changes brought about by the urnanisation of what were essentially rural communities.
It has never been a case of suggesting that people are UNABLE to create songs and music for themselves, just that circumstances have now changed for them to no longer do so.
Off to West Cork to see if I can catch sight of the Greater Spotted Cap'n Birdseye.
Jim Carroll