Holographic projection using spatial light modulators (SLMs) is unfortunately a dead end due to cost and complexity of manufacturing. There was a Cambridge startup a decade ago called 'light blue optics' (who have a promotional video narrated by Stephen Fry somewhere in the depths of the internet).

I don't think the technology ever got past military HUD for fighter pilots.

I do think that holographic projection is a feasible technology but it'll require a cheap method of introducing phase to thousands of pixels reliably. The computation requirements to generate the holograms is certainly something that can only become cheaper over time.