There are two separate issues here. One is how we choose to define God, and the other is what religious people actually believe.
OP was referring to "billions of people" with certain beliefs. Most of these people believe in God as an entity with a personality who intervenes in events on Earth. That kind of God doesn't have to exist by necessity.
On the other hand, if we define God as base reality, then God exists by definition. In that case why not just call it "reality" or "the universe"? When most people say they believe in God, I don't think they are saying they believe in the universe. I think they are making a stronger claim than that.
I don't get what the Romeo and Juliet example is supposed to show. The base reality for Romeo and Juliet is our physical world rather than the play world, and God is Shakespeare who exists contingently in base reality. Yes, it's impossible for them to prove that God (Shakespeare) doesn't exist. But what reasons could Romeo and Juliet have for believing that Shakespeare exists or that they are living in a play world rather than base reality? Unless Shakespeare explicitly writes evidence of his existence into the play, their claims are on the same footing as Russell's teapot.
OP was referring to "billions of people" with certain beliefs. Most of these people believe in God as an entity with a personality who intervenes in events on Earth. That kind of God doesn't have to exist by necessity.
On the other hand, if we define God as base reality, then God exists by definition. In that case why not just call it "reality" or "the universe"? When most people say they believe in God, I don't think they are saying they believe in the universe. I think they are making a stronger claim than that.
I don't get what the Romeo and Juliet example is supposed to show. The base reality for Romeo and Juliet is our physical world rather than the play world, and God is Shakespeare who exists contingently in base reality. Yes, it's impossible for them to prove that God (Shakespeare) doesn't exist. But what reasons could Romeo and Juliet have for believing that Shakespeare exists or that they are living in a play world rather than base reality? Unless Shakespeare explicitly writes evidence of his existence into the play, their claims are on the same footing as Russell's teapot.