But the human race is the most important species on earth. If it will go extinct, it will significantly affect all the other species on earth

The human race has an enormous impact over other creatures on earth. The biggest effect by no doubt and with no proportions to its numbers. Most probably bigger than the effect of all the other animals together.

As opposed to the enormous influence that is derived from humans' behavior, the human race biological "role" is supposed to be very minor. Considering its original place in the food chain and what was supposed to be its impact on the environment, the human race should have been a marginal species in biosphere terms.
Humans’ nutrition is not based on a specific species (they reproduce the animals and plants they eat by themselves) and vice versa, there is no other species that its nutrition is based on humans. Ecologically speaking, the human race is not supposed to be important. If humans lived in a sustainable way they were almost meaningless.

Without the human race infinite destruction ability, without the human race quick and aggressive conquest of the world while destroying most of the habitats of most of the species, without the destructive effect of humans’ waste, which is the result of their egoistic and immoderate lifestyle, without these factors, without these actualized potential to severely harm the other inhabitants on the planet, it would be hard to point out the changes if the human race ceased to exist.

Obviously, in the current state of affairs, the impact would be tremendous. A dream come true.
No more land robbing, no water and land pollution, no more oil drillings, ozone holing, garbage mountains. No more concrete.
And of course besides the ecological aspect, no more of the hugest and most violent exploitation systems ever in the history of this planet.
No more battery cages, no more raped cows, no more screwed brains, no slaughterhouses, no isolation devices, no bears on bicycles, no chronic hunger, no more babies who were born to a life of suffering from birth to death.

Therefore, the argument is absurd. What makes humans the most significant creatures on earth is their brutal and violent control over the planet, their destructive abilities.
These facts are arguments to annihilate the human race not to stabilize its position.

The "holiness" of human's life, as the modern society seizes it, is absurd. While humans argue whether birth limitation is moral or not, they justify cold-blood murder of non-human animals by claiming that they are destroying the balance of the environment. Humans are unproportionately more destructive to the environment than all the non- human animals combined. Nothing is even close to the destructive ability of the human race. There are no justifications.
The human race is the world's biggest "pest".