Yeah case fatality rate doesn't tell much if you're not doing at least randomized testing. From NYC's antibody testing COVID19 appeared to have about a 0.5% mortality rate, though that's likely an undercount since it only counts those who have died vs those infected instead of those who have died or will die from infections they already have vs those infected, since the time between first infection and death seems to be around 3-6 weeks for those who die. So a total morality rate of around 0.7% or 0.8% wouldn't surprise me much.