Good song or bad, love it or hate it, it sounds like a fakesong: in plain words, a song written in imitation of traditional songs and (this is crucial) palmed off on the innocent as the real thing.

Six years after the question was raised, nobody has produced the slightest bit of persuasive evidence that "Fakenham Fair" is

1. older than the 1960s.

2. has ever circulated in a form very different from the established text and tune

3. was even moderately well known in the rural or urban working-class community that it's supposed to represent.

4. embodies the attitudes and ambiance of that community, or any community other than that of sophisticated singer-songwriters

4. was ever known to anybody other than folk revivalists, revival aficionados, and (presumably) their non-revivalist source

If, on the basis of the evidence so far, "Fakenham Fair" is a "folksong" in any meaningful sense of that term, then so are "Oklahoma!" and "The Fool on the Hill." The only difference is that we're sure who composed those songs.

Of course, if consistency and reason don't matter, one may define "folksong" however one pleases. As has been done on Mudcat innumerable times because many 'Catters want the songs they like to be called "folksongs."