Suit yourself but the oil on a chain does something entirely different than steering fluid.
A while back I wondered why chain saws have their own oil. Why can't you just dump SAE 30 in there. When I looked it up I found that one of the distinguishing characteristics of bar oil is that it's designed to be thrown in your face. So, when I ran out of bar oil, I didn't hesitate to use vegetable oil. If you don't care what gets in your face and eyes, use any lubricant you like.