Politics seems to be a factor here, but I wonder how much of this has to do with popular culture.
Over the last 20 years we've been bombarded with metric tons of Apocalypse porn, a lot of it focused on killer viruses.
Most of those movies are unrealistic to put it mildly. Zombies. Deserted cities. Rotting corpses on sidewalks. Visible, palpable nauseating death.
This pandemic is nothing like those movies. I know of not a single pop culture depiction that looks anything like what we have now, except maybe the movie Contagion. And that's really a stretch.
So a lot of people have a problem when they see dire predictions and statistics that bear no relationship to what their own five senses are telling them.
There's also the problem of previous pandemics that sounded the alarm, but amounted to little in the US. SARS-CoV-1 and the Swine Flu.
All of this leaves the US with a population primed to expect a very unrealistic kind of pandemic, and already skeptical from previous false alarms. Throw in a president who not only sympathizes with the "hoax" perspective, but actively encourages it, and it should maybe not be surprising that we are where we are.