"In most places, one would expect far closer to fifty percent instead of less than one percent."

Mind I suppose it depends what country you are in etc but here in the UK I would expect a forum where a lot of the posters are folk musicians to be mostly left leaning. Certainly wouldn't expect it to be 50/50.

Likewise here in Scotland folk singers not only tend to be overwhelmingly left leaning but they tend to be overwhelmingly Yes leaning too. That is both on a national and local basis. And it wasn't just based on place of birth. The vast bulk of the English born folkies living and performing locally were left leaning and Yes leaning also. The local audiences on the other hand were far more mixed re the referendum.

I always wonder do left leaning (and here in Scotland Yes leaning) musos tend to be more drawn to folk music - or do people getting involved in the scene get influenced by the existing lean of the scene?

Though I agree there is no need for the insults etc. My own wife is a Tory voter (through nurture in SE England) and she was actively working for Better Together during the referendum. The other side have different political views but it doesn't make them evil or worthy of insults etc.