In addition to poor scholars, you have a problem of definition- just what is a deity, and when is the origin? Example: many deities are believed by researchers to have been actual people, or a conflation of a couple people who were treated as Saints, prayed to as intermediaries to the Gods, and then worshiped as Gods in their own right over the years- Lugh and Thor are in this category. Rastafarians worshiped Haile Selassie I as God- when he was not only still alive, but relatively young. Many of the African Diaspora adopt Gods and Saints from other cultures, and sometimes worship them as Gods in their own right. Chaos magicians, plus some other sects, may invent a God for a specific need on the theory that it is that fact of being worshiped that makes a deity divine, and so if they worship this newly invented God it will become a real God. Under that theory, the entities you refer to ARE now Gods! So it can be rather hard to tell sometimes whether an entity is a "proper" God.
peace,
ES