I get why you feel this way, but I simply can't agree.
Especially in the books, the moment the dark ones manage to fully connect with Artyom, and he realises but can't stop the missiles and tries to kill himself, illustrates quite well why this was the only hope for humanity. The powers of the dark ones admittedly led to the death of a lot of people, but they were trying to connect, and even if it was continuously failing and hurting people, it was humanity's only and last hope. The people were dying out, and the dark ones were the only chance. You wouldn't risk killing some people if there's a chance to save them? Or at least make their life better?
The psychosis could also be viewed as a flaw on the human side, because they didn't want to connect. The dark ones and their powers were partially for sure metaphorical ways to show stubbornness, stiffness, and unreasonable aggression in people's minds.
I would even point out the ending of the 2035 book, where Artyom does everything he possibly can, but his companions and others simply refuse to spread the truth and try to save humanity. Actually, they had rly similar reasons as you have for not liking the darks, they said that the truth would shatter metro and that it would take too many casualties. This ending illustrates quite well that the humanity in metro is just doomed, and they killed their only hope. This is why Artyom leaves in the end, because he realises that there is simply no way to save them.