In this question, the asker was looking for answers based on the original TV series of Star Trek.
Were there any named, blue beverages in the original Star Trek series?
One of the answers they received, was based on The Wrath of Kahn — a film featuring the same crew / actors as the TV series, but obviously not part of the TV series.
The asker then commented on that answer that they appreciated the answer, but were expecting answers from the TV series only, based on their use of "TOS". The question has since been edited to include a clarification that the asker is looking for answers from the TV series exclusively.
The usage guidance (tag excerpt) for star-trek-tos reads‡
Star Trek: The Original Series is an American science fiction television series created by Gene Roddenberry running from September 8, 1966, through June 3, 1969. It has acquired the retronym of Star Trek: The Original Series (Star Trek: TOS or TOS). The show became a cult classic in broadcast syndication during the 1970s, leading to five additional television series, 11 theatrical films (& counting), and numerous books, games, and other products.
Should the tag star-trek-tos include the same-era films?
As noted, the question has been clarified since. But was the asker right to expect answers from the TV series exclusively, based on the tag used?
Or can we reasonably expect the films made with the same crew and actors, clearly being in the same in-universe era, to fall under the tag as well? If not, what tag should we use for that?
Edited to add:
It seems I have misstated the intent of the asker. They used the term "TOS" in the question, even before their edit, and expected answers from the series only based on that. I misunderstood their objections to be based on the tag used.
Still, the question remains, does the term "TOS" and the accompanying tag include the TOS-era movies?
‡: Curiously enough, there's some more usage guidance regarding the use of the general tag star-trek to be found in the general tag info; I'll edit that into the excerpt since that's where it belongs.