Hes the second American pope. America refers to both north and south america. The United States of America only referes to a part of America.
He may be the first north american pope and the first pope from the united states of america, but hes not the first american pope.













Which continental model you use here is entirely irrelevant anyway because in neither model is north america referred to as just “america”. The only time that just “America” is used is to refer to the union of north and south america.
There is no country of America. There is the united states of america which would make the pope a statesman. So you can have the first north american pope, the first statesman pope, or just settle for second american pope.