No. For a single human being to unilaterally decide to destroy an entire species would be not only abhorrent but dangerous.
Arguably, if any other species recognized afterward that human beings granted authority and agency to individuals capable of such things, that species would be fully justified in committing genocide against humanity and wiping us out to the last man, woman and child - for their own protection against us.
They might do that but then they would be wrong, as the Federation and humanity are not homogenous, like the Borg.
No more wrong than Picard would have been, and not one bit more guilty of genocide.
Anyway, how homogenous might humanity appear to an alien? Fleas can probably tell the difference between other fleas, after all.