Meyer wanted Hornblower in space, not Rodenberry's world
...Which sort of ignores the fact that Roddenberry's world had indeed been Hornblower in space until he got involved in making ST:TMP.
The two early movies, Wise and Meyer's, both added never before seen technologies and stripped away some previously visited ones. This was hardly worth writing home about, as TOS episodes had regularly done similar nasty things to each other when mommy and daddy weren't watching. There was some incentive to make things "contemporary", but an even greater desire to distance the onscreen events from the daily news and rather liken them to bygone, fondly remembered things. Even Meyer didn't want "contemporary" with his fine-tuning, he wanted 1960s and sometimes 1940s, or their Hollywood equivalents...
You can't really see the forehead of the translator in ST VI, I don't think.
Definitely not in the movie (all you can tell there is that the mustache looks roughly similar). In some backstage pictures, perhaps?