Necessities of 3D consciousness

[Monica]

The potential for abstract thought seems to be the main thing that separates us from 2D beings, and perhaps human fetuses.

A 3D+ entity does not lose their density when their physical vehicle is unconscious, such as a person who is comatose. The same would apply to a human fetus. The entity inhabiting (or who will inhabit) that physical vehicle is of a certain density; the current state of its physical vehicle has nothing to do with the entity's density.