Here is how I see things.
I can think 'this is my projection, my existence, you exist because I am projecting your existence' however, so can you. Now my wife's father died not long ago but he could've been thinking the same. I still exist after his passing. Therefore there is a common ground we all exist on or are projected to - the universe, milky way, solar system, earth...
We can observe things down to microscopic level, with electron microscopes we can see down to a hazy atom level (if anyone has images please send me a link).
If there was anything projecting in a holographic sense or even into our minds the earth or what we do through our lifetimes, to project on such a detailed level would IMO, take more space (for the information on what you are projecting) than what you are actually projecting.
But, it looks more like that atoms or even the subatomic particles are the material of 'projection'. Energy they are made of and with energy they can change. Each particle 'knows' how to interact - Laws of Physics and has substance due to energy.
The particles then do not require external SW/programming they simply interact according to strict rules with anything they encounter, no memory per particle either. Collectively, the universe with Laws of Physics in place is a projection/place (very real - but non-existent

) for our consciousness! It is our consciousness that is projected through the tinniest of wormhole/singularity/???/planck length to 'control'/???/experience THIS. From the 'other' side, our existence (with the extra time dimension?) looks like a weird 'energy' oscillation??? anything physical/time dependent is inconceivable and perhaps just as big a mystery also. hmmm
Just a thought...
Earth is but a playground for the creator / 'cause of existence' / life force? Maybe..
Through us 'it' gets to be fully everything and experience the creation?
No, I am not religious. By 'creation' I mean the universe begining with perhaps the big-bang? But that's another topic...