The universe only renders what you're looking at.

Measurement changes the outcome. Particles don't settle into a definite state until someone observes them.

A video game doesn't render the room behind you. Apparently, neither does reality.

Two readings.

One: optimization, the universe conserves compute and only draws what's observed. Which means you're inside something.

Two: we confused a metaphor for a mechanism. Physics is strange. Strange isn't the same as simulated.

An honest universe wouldn't care who's watching. This one does, or we made it look that way.

Sit with this one.