. . .The very existence of the Atoz replicas does suggest a high level of 3-D imaging technology. . .
I'd never thought of the Atoz replicas as being holograms, I've always assumed they were some sort of service androids or robots. Laser based holography was still in its infancy in the 1960s, and a Nobel Prize in Physics wasn't awarded for development of the process until 1971.
Holodecks never seemed to be a technological concept in TOS. Simulated environments were usually explained as some sort of telepathic influence.
The 1976 film Logan's Run
made a big deal in its promotional materials about using actual state of the art holograms in the production, and I saw real examples in museums during the early 70s. There was no real lifelike movement as ST and other shows present. The illusion of movement was present only if the observer changed his viewing perspective.