Isso foi abordado em uma entrevista com o showrunner Brannon Braga. Resumindo, eles reconheceram que o episódio do universo espelhado no TOS era favorito dos fãs e não queria fazer algo que fosse comparado desfavoravelmente.
However, there was a specific line they never crossed. In response to a question on why they never did a Next Generation mirror universe episode, Braga responded:
"We were a little frightened at doing it, and doing it badly, and maybe never really figured out what the Next Generation take would have been on it."
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