Here's a halfway decent summary of the various controversies surrounding the divinity of Jesus in the first few hundred years. You can see the variety of different ideas advocated by a variety of Christians in that period. Martureo's position is that only the winners in these debates count as Christians.
https://en.wikipedia.org/wiki/Christology
In my experience, the average Christian is not aware of these differences, can't articulate the orthodox position, and often say that they believe things which were declared heresies in these various councils.