I think the image gained popularity due the whole 'starving artist living in a freezing attic room but committed to their craft', Parisian left bank, arty scene.

That said, there's a reason art therapy (and also dance and drama therapies) are so useful when dealing with mental health issues. Having a non-verbal way to express your emotions can be invaluable. So I think there is a tendency, a thread of commonality with a certain number of artists, though as you say, by no eans all.

It could also be said that a propensity towards experiencing any and all emotions strongly gives certain people an edge when it comes to creative, artistic work.

Good piece. Thought provoking.