I don't see how the at-worst number can possibly be 200K. If you're talking about the U.S. alone, we're at 75K deaths with 1.25M known cases. Assume there are actually 10x that of actual cases, that's still only 12.5M infected so far. With 125M infected (well under half the population), we would be at 750K deaths.

To get to 200K worst case deaths you'd have to assume we've already had something close to 100M infections.

(Also based on the excess mortality data, the current COVID death numbers are probably underestimates)