To follow up on the above comments as well as on my earlier one: The slapdash nature of the episode is the main reason for dilution of the impact of any meaningful speeches that the script had to offer. By the time "The Way to Eden" was produced, the end of production was coming up fast - this is, what, no more than four episodes earlier than "Turnabout Intruder"? - and no one cared about the story-editing, scene-to-scene continuity, etc., by then. (Or the people who did care had already left: The Gerrold 1973 book says explicitly that D.C. Fontana "quit when it [her episode "Joanna"] became 'The Way to Eden.' ")
The music, on the other hand, was very much non-slapdash and required some careful preparation by its very nature. Likewise the musical instrument design, the egg logo on the costumes, etc.
Oh, and another not-so-bad thing that happened in autumn 1969: the Vietnam Moratorium protests began.