The thing is that Voyager and Star Trek In general are fictions, we don't need to agree with their conclusions to be entertained by them. We must not lose sight of that. Some of the things that we are shown are entertaining yet if applied to real-life truly horrible and detestable. We don't need to agree on what they are but we can always debate it. IMO, given the impossible facts as presented, I mean mixing two (three actually) DNAs already strain credibility beyond reason but unscramble these DNAs and reconstitute the people goes beyond even that!!! To quote Asimov is it worse than impossible, it's ridiculous. Anyway, Janeway wasn't given a deadline about the "unscrambling" procedure she could have done it immediately or waited till they came back to the alpha quadrant or anytime in between so her murdering of Tuvix was not only unwarranted but a bit precipitous as if she was afraid that if she waited any longer people would start to argue that there was some merit in letting Tuvix live. That's cowardly. But the truth is that Voyager hits the reset button at the end of each episode and so we have a different Janeway for each. We may detest this one but maybe we'll like the next one. Who knows?