The problem are not the few special cases we see even in this thread, the problem is that we have places like India or Brazil which, for one reason (not enough money) or another (moronic president), have very few people vaccinated and that is already coming back to bite us in the ass, the english variant replaced the original virus of Wuhan and now the indian variant is replacing the english one since it is even better in spreading than the mutated english one. Also, since now this new variant is taking ground in England, who is the most vaccinated country in Europe, it seems that Astrazeneca, at the very least (since the UK was vaccinated almost only with this one), is not effective against it.
The point is erasing the virus worldwide before it has the chance to reproduce too much and so evolve and develop new variants better at spreading (and immune to the current vaccines) than the old ones otherwise we will always be running after the virus and his new mutations. But I know this is wishfull thinking.