Under-reporting cases in one thing, but I think the real issue is under-testing. Governments around the world simply don't have enough tests available.
Even on that cruise ship, with 3500 people on board, they barely tested them. Only people with fever got tests.
Others were simply walking all around the cruise ship, carrying coronavirus, completely undetected.
That's what happens when sick people aren't really all that sick. People should really calm the fuck down.
2% mortality rate? Sure, out of the people who are sick enough to see the doctor. There's probably tens of millions of people infected with nothing more than a slightly runny nose who just think they have the common cold.
There's official underreporting and then there's just plain general unawareness.