On this very topic, this might be one of my most favorite videos ever single-handedly changing my understanding of holograms: https://www.youtube.com/watch?v=EmKQsSDlaa4
(Kind of like to get into old-school holography — now that I can actually afford a laser.)
One could quibble and claim that the nature of the 2D encoding in the case of the holographic universe is closer to that of the original concept, but it’s a weak defense at best. After all, the holographic universe isn’t even just about light, it proposes that matter and space itself is only apparently 3D.