Then do it. I write hubs on subjects that interest ME. Obviously, I hope they will be of interest to others as well; but, I do not let what I think others will read steer me in any particular direction.
Authors should write about what interests and motivates them. The best and most creative writing is done when the author is moved by the subject matter. No one has only one interest in life; so, why should an author stick to one subject in their hubs.
If it moves you, write about it.