Oddly enough StephenH my post was bang on topic and had nothing to do with Millar's politics as you put it, the point of the post is what is said in the last sentence. The post is about singing in an accent other than your own normal/natural voice, GUEST Cj pointed out what he honestly thought of Millar/MacColl's recorded singing voice in response to Jim Carroll's post.

On the well worn topic of "what is folk music" I am generally fully in agreement with what Jim Carroll has to say on the subject. In the course of my lifetime the genre that sparked my interest has been totally and detrimentally highjacked, to the point that many "Folk Clubs" should be prosecuted under the trades description act as in Jim Carroll's own words on going into a folk club today you "Never seem to get what is written on the tin".

To answer your specific question:

Is it really so horrible to sing in an accent that you have been surrounded by and nurtured in for a good deal of your life - even if it isn't your natural speaking voice?

Yes it is horrible, what you are describing is mimicry, or what PC enthusiasts would term cultural appropriation. The most practiced exponents of this that I have seen and heard are live bands out in the far east, generally they are from the Philippines, on stage while performing singing songs written in English they are word perfect, close your eyes and you would believe that you are listening to the original artist. Go over and talk to the band to compliment them on their performance and you are answered in pidgin.