It more or less started after Paramount removed Roddenberry from active involvement with the movies and be began a smear campaign against Nick Meyer and Harve Bennett summarizing that everything that was in TWOK violated the "spirit of Star Trek" or some such. Then when TNG came around he used this Spirit of Trek as the rules of how the show needed to be.Where has this "Gene's vision" originated?
Was it something Gene himself put out there or created by people who want to categorize things...
Of course at this point, Gene himself was seriously diluting his Vision anyway. Take for example the episode Justice which was originally pitched as a rather grim and serious storyline about rigid adherence to strict laws, but while discussing the script, Roddenberry repeatedly requested every second scene include a random orgy for no real reason. As a result, we got one hella weird episode, which started as something grimdark, was livened up with orgies, then reined in because there's only so much you could do on 1980s syndicated television.