We know very little factual information about Shakespeare. In fact, all we know for sure can fit on a small index card. Most of what we know is recorded in history books in the form of wedding certificates, birth announcements, employment records, and publications. As he becomes a more well-known playwright, we have criticisms. Of course, we always have his plays...through study of these writings and his poems, etc. we can come to some conclusion as to his inner workings and opinions.
I think this is an excellent question. We don't really know enough about Shakespeare, and we should wonder about what we already know, the information we have taken for granted. It was a long time ago, and there are many who could have benefited from Shakespeare's name.