Let's look at this another way. If we accept that a photon travels from the sun to Earth in zero time through zero space from its FoR, then we accept the photon does not exist in a universe with space and time. It is the observer who lives in this world. Spacetime emerges when an observer is moving at less than c.

If all that exist are photons, then each photon is moving through zero space in zero time, and there exist no observers to contradict this. So how is this any different to all photons existing in the same place at the same time? That's how they "observe" the universe.

Spacetime is something that exists to an observer. A photon is not an observer, as it has no clock.