The risks of not freaking out and it decimating the populace should easily outweigh the risks of freaking out and it not having an impact. It's very difficult to even rationalize the latter because a freakout might mean the impact is negligible.
At this point more than enough data exists to show the population will suffer ~1% losses. We shouldn't need 10% to freak out. Not to mention long-tail fatalities that might arise if it becomes an annual virus like the flu. When all that had to happen was people treat it seriously to begin with rather than saying "But the flu is way worse".
Maybe, or maybe not. Let’s say it’s 0.5% fatal and largely only to folks who are older and have comorbid conditions. Instead we panic 100% of people, leading to mass hysteria, loss of livelihood, global recession, military zombie apocalypse lockdowns and so on. What if our response causes more harm? It might well.
Proportionality of response matters and so do second and third order effects. What if all the above causes more than 5000 suicides? Did we win?
The difference between 0.5% and 3% case fatality rate is in large part determined by whether hospitals become overwhelmed, and that in turn will be determined by whether we take immediate and widespread preemptive action to reduce the exponent of the infection curve.
