I think its the lack of Evas thing that makes it should not be... its the whole lack of details and source conflict issues that 'Should not be' this thing... as it is now its rather hard to fix it. There is just too much missing to do something with. Its the nebulousness that hampers it. The extinction events is made of 'um what?' If we fill in the root details that are causing issues its recoverable.
For instance: If some guys drugged her into a psychedelic stupor and she heard accents of Russian-Chinese-Indian , The extinction event could be that closed space giant are ever rampaging in the area or those countries had large chunks of the population swallowed into closed space. Either way NERV (or whatever) is actively hunting down loose CSGs and Haruhi is drugged up to keep whatever they did in the failed capture incident screwed her up bad enough that she has to be sedated or bad things happen.
So basically this is a 'Should not be' by lack of coherence rather than the idea itself being worthless.
For instance: If some guys drugged her into a psychedelic stupor and she heard accents of Russian-Chinese-Indian , The extinction event could be that closed space giant are ever rampaging in the area or those countries had large chunks of the population swallowed into closed space. Either way NERV (or whatever) is actively hunting down loose CSGs and Haruhi is drugged up to keep whatever they did in the failed capture incident screwed her up bad enough that she has to be sedated or bad things happen.
So basically this is a 'Should not be' by lack of coherence rather than the idea itself being worthless.