I've seen a meme recently that equated the spread of COVID to a group of people working on projects; one person brings glitter, and now all of the projects have glitter on them. Similarly, I've seen good-intentioned people make generalizations such as people are choosing between haircuts and their deaths. In both of these cases (and many that are similar) the use of overstatement is meant to capture people's attention, but it instead leads people who are already prone to disagree with the argument a credible reason to say that misinformation is being spread.
COVID doesn't spread like suggested in the glitter meme. Even if a person with COVID were to be a part of a gathering, there are a number of factors that both increase and decrease the chances of people getting it from that exposure. Although COVID has been proven to spread significantly faster than the flu or common cold, practices such as wearing a mask (especially if it's the person with the virus), thoroughly washing hands (especially before eating or after using a public restroom), and avoiding touching the face will all reduce the chances of catching COVID.
Nor will COVID kill everyone who gets it. Perhaps it's the fault movies and TV shows that deal with diseases--particularly zombie movies--but many people in our society see diseases as instantly infectious and almost always fatal (without a last minute cure delivered by the hero). This leads to overstatements such as the one about the choice between getting a haircut or dying. COVID deniers point to the many haircuts that have safely taken place and mark the whole thing off as a hoax.
Even top ranking officials have pointed to the current daily death count (which is lower now than in April) to make it seem like everything is over despite the rising number of cases. They forget that it usually several weeks from the point of COVID infection of fighting the disease before people die from it. They also forget that many of the increased cases are currently in younger people who are less likely to die from the disease; it's when those younger people infect their elderly or immunocompromised friends and family who are significantly more susceptible to dying from COVID that the death rates start to rise again.
Because this isn't like a zombie story where if a person is bitten or scratched they will always become infected and will die (and become one of the undead), people are having problems dealing with a slower, not-quite-as-lethal, but still terribly serious disease like COVID. We humans don't have the attention span to realize that increasing infection rates today mean high death rates (not tomorrow) in about another month. As the overstatements are not proven to be true, people begin to lose faith in the entire concept.
I'll end here before I overstate the power of overstatements.