Galaxies? No. Universes? I don't know. Do you?
I'm pretty sure there is no man in the sky creating galaxies. Lol.
If he was how could you perceive him with the senses?
it would be like an amoeba deciding that there was nothing else going on out there except what falls withing its tiny range of perception.
He's no more "real" than the various gods that the Greeks or Pagans believed in.
When speculating about Greek or Pagan gods you should keep in mind that people used to believe that a human being could be a god.
Are human beings not real even if they are not gods?
I'm not talking about "kings" or "emperors" obviously. I'm talking about their beliefs in supernatural entities of which there was absolutely no evidence.
But still how could people living on a small rock orbiting a small sun in a small galaxy in an obscure part of the universe be capable of perceiving whether or not a Being capable of creating all that exists is real except if he should choose to reveal himself to your mind?
If that is the case then a pure state of mind should be aspired to first before anyone can have any reasonable expectation of a visitation or revelation.