the fact that certain songs are 70 years old is not really relevant it is not the age of a song that makes it a folk song.
the whole point of oral tradtion quote
a
community's cultural and historical traditions passed down by word of mouth or example from one generation to another without written instruction.
buddy holly AND BEATLES songs are written down and always sung without alteration to the lyrics, therfore they do not fit under the 1954 definition, the only occasion they do, are when they are ADAPTED AND ALTERED by football crowds.
the folk do not choose anything they are fed banal pop by the media