Earlier quoted context omitted.
This is why they're taking it slow; they're not worried about knock on issues with our herd immunity. They're worried about ecological collapse. https://en.wikipedia.org/wiki/Four_Pests_Campaign "The "Four Pests" campaign was introduced in 1958 by Mao Zedong, as a hygiene campaign aimed to eradicate the pests responsible for the transmission of pestilence and disease: the mosquitos responsible for malaria; the rodent…
Its important to differentiate b/w the plans of a politician and the plans of research scientists who have done actual work in this area. Mao's plans seem to have been a hare-brained solution to China's problems (and they're not the only one. Cultural Revolution and the Great Leap Forward cost more lives than both the world wars... and they were all Chinese lives).
Not really, because the general public won't take such care with the differentiating. The more scientists deliberately exterminate or cull animals, the more the public will grow accustomed to the idea of humanity taking such an active violent role in the environment. And the more the public grow accustomed to that idea, the more they'll be willing to fall in line behind politicians who try to do the same. Particularly when those politicians claim science as their justification (numerous disastrous examples in the 20th century.)
The ethical analysis performed by scientists looking to justify exterminations should include the social impact of their actions. Scientist and engineer sorts often loath considering such factors.