I went back through the conversation and I'm not sure what the original point is regarding new species. Could you spell it out for me?
Well, then in that case there weren't that many of them in the other shows either.
That DS9 only bothered really fleshing out characters from existing alien species TOS and TNG had already introduced, or from the Dominion Aliens.
Therefore Voyager shouldn't get insulted for not being able to flesh out dozens of alien species over its run, especially since the premise meant they'd never be able to anyways.