Agreeing with your point: there is only one human virus thought to have been successfully totally eradicated: smallpox, which plagued humanity from ancient hist

Agreeing with your point: there is only one human virus thought to have been successfully totally eradicated: smallpox, which plagued humanity from ancient history until the late 1970s. But herd immunity due to widespread (if imperfect) vaccination gets you much of the way there. Assuming flu vaccines continue to work, there probably can't be flu outbreaks that kill tens of millions of people as there have been in the past.