Isn't that a simpler explanation of reality than the zillions of particles all existing simultaneously in this massive universe?

Some sort of simple primal generative AI construct that just feeds a conscious experience for one. You. Nothing else is real. No one else is real.

Something like that would be an infinitely simpler, than running the physics and conscious experiences of this unimaginably large universe we think we're in.

explains how fringe details don't make sense, like no one knowing what oracle does exactly

Simplicity is only relevant to humans (and other animals that evolved into trying to forecast their survival). Most of the universe seems to prefer chaos. So no, from a universal perspective, there is no reason for reality to be simple or elegant.