I am sure there is a great deal of high standard singing in many folk clubs. But I cannot help feeling that there is something 'untraditional' in an emphasis on 'standards' if we are talking about 'ordinary people' making music for their own amusement.

This emphasis on 'standards' as evidenced by one 'spectre at the feast' may be down to the approach at the critics group, which seems to me to have been a long way from 'traditional', involving as it did Stanislavsky method acting and so on. Indeed, one account says that MacColl "set about the Herculean task of trying to drag British folk music into mainstream culture. Frustrated by the dreary amateurishness of folk song performance, he decided to establish his own centre of excellence to professionalise the art."

https://carthyarchive.wordpress.com/2012/01/03/how-folk-songs-should-be-sung/

The key here is 'professionalise'.

I don't particularly object to professionalisation but let's not imagine that it is 'traditional'.