I have to disagree, it is in my opinion ignorance of the subject,as I said Lea Nicholson,was playing Beatles Music the Dam Busters march and doing it well[and getting paid for it] etc etc in folk clubs all over the country way back in 1973.
If the reviewer has led asuch a sheltered life that he hadnt encountered other music than trad folk on a concertina he should not be reviewing
this reviewer lived in Nottingham,at that time I used to see Reuben Shaw,playing his concertina in the co op folk club in Nottingham[his repertoire was the popular music of the twenties]he was incidentally complimentary about my playing of non folk stuff such as Woodland Flowers ,Yesterday,Washington Post etc
this reviewer had people right under his nose in Nottingham,playing non folk music.
he is supposed to be reviewing , why? i is it not a good review,because the reviewer tells us more about himself than the music
what the reviewers job is,is to tell us whether the playing is good or not,not to give his opinion about whether it is incongruous on a concertina.