We can hope that “they” don’t “just slip it in the yearly flu vaccines”; on a good year vaccine utilization of flu vaccines might break 30% even when there is a global influenza pandemic brewing.
And rinderpest, and we were a hair’s breadth away from eradicating poliomyelitis until religious fundamentalists whipped up a fury about vaccination being a CIA plot which the US of course obliged by actually using the vaccination campaign as a cover.
Regardless, given the propensity for SARS-CoV-2 to reside in multiple mammalian hosts, it seems unlikely that it is ever going to be completely eradicated, and the best we can really hope for is a particularly infectious version that has only very mild effects, in essence naturally inoculating the population against more virulent versions. Immunity from vaccination is actually really effective (particularly for a rapidly developed first generation vaccine) and immunity appears robust in many people many months out but we’re still seeing signs of waning immunity in some people–particularly the elderly and immunocompromised individuals–and breakthrough infections in low double digit percentage of the population, so the virus isn’t going to disappear. But we’ve never achieved herd immunity with chicken pox, and more half the world’s population is infected with herpes simplex (HSV-1 or -2), and civilization continues to move on, because while these diseases aren’t inconsequential, they are manageable through vaccination and therapeutics.
It is frustrating that so many people refuse vaccines that are available to them, often not even out of any misguided principled objection but just because they want to “see how things pan out”, but then, nobody ever made money betting on the rationality of humanity. To reject a prophylactic treatment that people worked tirelessly to develop at a cost of many billions of dollars feels like yet another step toward Idiocracy but it’s really just a drop in the bucket compared to all of the other stupid and illogical things people say and do.