OP, ask yourself: if you invented competition to the traditional banking and monetary system, would you like your identity to be known?
the entity using the satoshi pseudonym is one person. that is established.
Any conclusive investigations regarding if he was indeed a single entity or not?
Yes,satoshi would have thought that he would face serious threat from banking sectors since his creation is to be the worst nightmare for bankers.He is a single person.He just wanted to free people from depending on the banking sector.