As I recall, in the 1960-1980 time frame, the explanation was the "hippie" reference. No word at all about the Judge vs Charles Taze, of course. An interesting sidelight was that black brothers were allowed to have a moustache (but I think not a full beard) because of "cultural" reasons. This really meant that nobody wanted to start anything with racial overtones.
There was also the critical issue of the width of the tie. It was grossly anti-theocratic to have a tie less than about 1-1/4" or greater than about 2" in width. But, black brothers again were exempted and allowed to wear those white shirts with really tiny collars and really skinny ties about 3/4" in width. (Think Malcolm X to get the picture) Us guys in the white congregations were of course insanely jealous on both counts, even if we were too young to grow any kind of facial hair at the time.
Full beard for me now, but neatly trimmed -
James