> How can you even claim an "average death rate" when you don't even know how many people were infected, had mild symptoms, and recovered without reporting it to anyone?

We can either throw our hands up and give up or we can do the best with what we have. So, what percentage of cases do you think are unconfirmed? You can adjust my math with that and see what those rates are. Those numbers still stay scary unless you assume a 90% unconfirmed rate, at which it equalizes for young people compared to the flu but is still 10x or more for some age groups. The point being, even accounting for underreporting this is still much more deadly and allowing it to spread like the flu would result in many more deaths.

I haven't seen any reliable numbers given about the underreporting rate, so if you have seen any that would be interesting!