COVID-19 hit the people who have already had their children, and those children are not in the risk group.With vaccines or without, there is no reason to think COVID-19 will impact human evolution.
Polio is mostly a child’s disease. Would you want your child or family to go through natural selection?
About 50% of live-born children died before reaching puberty in Europe in the 19th century. Currently, the survival rate is over 99% and the reason for it is not magic.
We have been making people fit enough to survive through medication and care for thousands of years, perhaps even before our ancestors were homo sapiens.
It is not a coincidence that if they need, virtually all of us will take care of others; may that person be your sister, your child, your friend or sometimes even just a stranger.
Humans are where we are thanks to natural selection. In human history, those communities that did not take care of each other had perished with no descendants.
Letting people die of diseases, or any other natural condition hoping it will help our descendants, would achieve nothing but adding homo sapiens to the long list of extinct species.