Roddenberry had nothing to do with the final season of TOS, remember? This was all Fred Freberger's garbage and anyone who's seen SPACE:1999 can recognize his "brand of it."
It's not entirely correct to say Roddenberry had nothing to do with any third-season script. He was involved in early decisions regarding script assignments and discussions about first drafts, at least for the first eight or nine scripts of the season. I personally saw memos to and from Roddenberry about "The Empath" and "Is There in Truth No Beauty?" in the archive of George Duning's papers at the USC library when I visited there in 1985.
This is not to say he approved any of the episodes in final, produced form. But he was involved in some of them before he left.