Novelty means modest infectivity, before it means severity. The author's facts aren't wrong, but could severely mislead as currently characterized by him.<p>We started COVID-19 in 2019 with a novel and rather incompetent (at infecting humans) confronting a novel (to the virus) host incompetent at dealing with this particular virus. For zoonotic viruses, this is a pretty standard beginning, obviously. The chances that a virus previously not encountered will be able to easily and immediately trounce human immune-defence-in-depth it has never seen is awfully small.<p>A precious time not to be wasted... but we in the West simply threw it away. Only when (white-like-us) Italy was hard hit did we begin to wake up.
Very quickly, soon after getting to North America if not sooner, mutations altered this picture and then over months further new strains provided considerably more transmissibility.<p>That much more potent second and third waves would follow should have been clear from first principles and past experience (say with Spanish Flu) but the US did almost no testing for variants, so they weren't looking for them, and the public wasn't warned properly.
One of the primary lessons of the pandemic is that an enormous amount of very basic research on virus pathogens which should and could have been done even a century ago, was never done. It wasn't sexy.<p>The author's argument that we likely very much underestimate the value (including epigenetics) of past exposure over decades to current immune response is welcome. The previous idea that strains weakened so as not to kill their hosts is certainly true over periods of centuries; but as late as 1946 the most frequent cause of death was still Syphilis, which was novel to Europe in the late 1400s.