The risk management pencil pushers never factored in a Black Swan, because it can’t be factored in, by definition.
You simply cannot spend the money to build the capacity of everything needed for a black swan. It would sit there unused for decades until it was all obsolete or expired and discarded.
The Brits, though, apparently have 1/7 of the per capita ICU beds we do. They decided to be far less ready than we are.