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Jumping into the Tuvix debate with @AOC about the Star Trek Voyager episode where Tuvok and Neelix were accidentally combined into one wholly new person during a transporter accident. Tuvix didn't want to be separated, but ultimately Janeway forced him to. So who was right? https://twitter.com/AOC/status/1324199525666430977
The short answer is nobody was right. Tuvix didn't consent to be separated back into Tuvok and Neelix, arguing that it would in effect kill the new person he had become. But Tuvok and Neelix didn't consent to be combined, and allowing Tuvix to remain essentially killed them both.
Tuvix's existence was an accident. If Tuvok and Neelix had died in the transporter instead of being combined, they would be no more or less dead than if Tuvix was allowed to remain. But Janeway's decision to separate Tuvok and Neelix - thus killing Tuvix - was an active choice.
Erring on the side of doing the least harm, ethically Janeway should have allowed Tuvix to remain. However, you also have to consider that Voyager was on the opposite side of the galaxy. They had no way of knowing if they'd ever make it home, and needed every available officer.
Tuvok was Voyager's tactical officer, and absolutely critical to the survival of the ship's crew. Allowing him to stay "dead" when Janeway had the ability to bring him back could ultimately have meant the difference between life and death for hundreds of crew members.
Did Tuvix's autonomy in the present outweigh the autonomy of Tuvok and Neelix in the past and the potential impact their "deaths" could have on the success of Voyager's journey in the future? Maybe. Janeway's decision to separate Tuvix is extremely divisive among fans, even now.
Ultimately, it was a no-win scenario that's far more interesting than the Kobayashi Maru test they give to Starfleet cadets at the academy. And given all the factors involved, I'm not sure it's a choice that anyone can truly judge unless they've faced it themselves.
I'm sure the Starfleet principle that the needs of the many outweigh the needs of the few (or the one) factored heavily into Janeway's choice. Personally I think her decision was strategically correct but ethically wrong. But I do know Spock definitely would have agreed with her.
