A Midwestern Doctor, has written on the smallpox vax, which contrary to the mainstream vax propaganda was highly controversial at the time. The received view is that the vax was a miracle drug that saved the day and led to the elimination of smallpox, so if the vax could do tht for one disease, it could do it for all of them. That generalisation would make an objective scientist suspicious, since it hardly follows. As shown below, the historical data shows that the smallpox vaccination did not work as promoted and tended to increase rather than decrease the occurrence of smallpox. In anticipation of Covid, harsh mandates were implemented to get even more people vaccinated, and riots broke out.
It was improvements in public health that led to smallpox disappearing, not the vaccines, although Big Pharma of the time claimed this as a victory. An even bigger killer than smallpox was scarlet fever, where there was never a vaccine developed, but which also disappeared with improvements in sanitation and living conditions. Just like smallpox.