The thing that bothers me about the idea of the "Ruliad" is that it's completely unfalsifiable. Even if we existed in a reality where true randomness existed, or computational irreducibility wasn't a given, you could always argue that what we observe is just one finite local slice of that Ruliad where things appear to be deterministic (or computationally irreducible) due to our boundedness as observers.

It's basically the modern equivalent of "turtles all the way down" because it pretends to explain the nature of reality by extending our definition of reality to fit within an all-encompassing mental model that only makes sense on a surface level.

Granted, the words "universe", "multiverse", etc. are insufficient in describing everything in a way that includes everything we currently want to include, but giving a new name to that abstract idea of "everything" isn't itself a compelling argument to also say that everything exists as a static construct and that everything is computationally irreducibile and deterministic at a fundamental level. Yes, that makes sense in a physics simulation, but in reality, we don't know what we don't know. Placing the unknown in a conceptual box doesn't imply that it's now known.