I think there is more symbolism in this episode than is normally acknowledged or commented upon. That they choose Apollo as the particular Greek god to meet somewhere out in space, apparently as if he had been waiting millenia for the earth creatures that resemble himself to develop spacefaring technology and eventually find him... while in reality, after millenia of looking at the night sky, naming the stars and planets, telling our seasons by them, and thinking up fables and superstititions about them, the program to actually land and walk on another world happened to be the Apollo Moon Program. And the moon, only feasibly reachable within the recent decades before it was actually done, and once thought a god 'himself' by many cultures, proved reachable, after all, without any god. So, as we were to soon reach what was thought a god, it was in fact not a god, nor was a god's help needed; it was pure applied science. And knowing Roddenberry was an agnostic, perhaps an atheist, the point is clear: there are powers and forces in the universe, but it was humans that invented the god hypothesis to explain them on the elementary level, and this hypothesis can be destroyed, and that will be one facet of our scientific legacy. But the god he really had in mind, of course, was not the loyal friend of (loser) Hector of Troy, but the God most of the western world eventually turned to, originally of the ancient Hebrews. He is not necessarily saying that that God (or his race of beings) may be found some day as having been Wizard of Oz type "humbugs," but it is at least such a thought experiment to that effect.
As for Apollo being a potential tragedy (slavery; everlasting indebtedness in the episode) we would have to deal with... this episode (and presumably its inception) came a few months after the launch pad fire of Apollo 1. The moon program, as is well known, had progressive success in the early and mid 60's and became overconfident and began to 'move too fast;' that is, too fast for safety in order to meet the deadline of landing on the moon before the decade was over. And in hindsight, many historians look back and say a disaster was inevitable. To phrase it in correspondence with the episode-- If we don't get Apollo under our control, Apollo will ruin us; even if we destroy the 'end of the decade' objective, we must get a grip on Apollo, and we cannot place ourselves forever in debt to 'him.'
I think the above 2 paragraphs are more of what ST was attempting to say, rather than anything in particular about the ancient astronaut theory, though that certainly was around at that time, just before Erich Von Daniken published his first book. Indeed, the 'getting back to nature' theme was more pronounced, but with the addition of "not because we are being forced to." There was a movement, of course, at that time of getting away from the unfriendliness, the pollution, the overly-mechanized cities, and living more in harmony with nature. Hippie communes, 'bedroom communities' with homes on large tracts, time-share getaways, et al, were manifestations of this idea. And shows like Green Acres parodied the idea. Perhaps "Who Speaks for Adonais?" was also another angle of parody of "away from mechanization; back to nature," or "weren't the ancients lucky to have no other way?" (the answer being obvious).
As for Apollo being a potential tragedy (slavery; everlasting indebtedness in the episode) we would have to deal with... this episode (and presumably its inception) came a few months after the launch pad fire of Apollo 1. The moon program, as is well known, had progressive success in the early and mid 60's and became overconfident and began to 'move too fast;' that is, too fast for safety in order to meet the deadline of landing on the moon before the decade was over. And in hindsight, many historians look back and say a disaster was inevitable. To phrase it in correspondence with the episode-- If we don't get Apollo under our control, Apollo will ruin us; even if we destroy the 'end of the decade' objective, we must get a grip on Apollo, and we cannot place ourselves forever in debt to 'him.'
I think the above 2 paragraphs are more of what ST was attempting to say, rather than anything in particular about the ancient astronaut theory, though that certainly was around at that time, just before Erich Von Daniken published his first book. Indeed, the 'getting back to nature' theme was more pronounced, but with the addition of "not because we are being forced to." There was a movement, of course, at that time of getting away from the unfriendliness, the pollution, the overly-mechanized cities, and living more in harmony with nature. Hippie communes, 'bedroom communities' with homes on large tracts, time-share getaways, et al, were manifestations of this idea. And shows like Green Acres parodied the idea. Perhaps "Who Speaks for Adonais?" was also another angle of parody of "away from mechanization; back to nature," or "weren't the ancients lucky to have no other way?" (the answer being obvious).