The Jews knew they weren't the only people on earth, they just believed they were the only ones God cared about. But you do have to give them credit for devising a mythology that pretty much took over half the world (with variations and modifications). Nobody today knows or cares what nonsense our European ancestors believed.

What the Jews contributed to religious thought was a God that demanded certain behavior and published rules based on a moral and ethical code that applied to everyone. Prior to that, gods were just egotistical selfish bullies that could be bribed and that had to be appeased or they would crush you out of spite.

In order to more closely match reality, what we really need is a religion based on a totally indifferent God who doesn't care what we think or whether we worship him or not. This is what we today call Deism, or the faith of many of this country's founding fathers. It separates the eternal question "How did this all come to pass?" without having to resort to "What do I have to do to keep this guy happy?"