Frankly though, I wish the term used was “water resistance” and not “waterproof”. That semantic annoys me.
Better is to use an ingress protection code, which provides standardized ratings for exactly how dust and water resistant a device is. Apple does use IP codes and rates the latest iPhones as IP68: dust-tight, submersible at a depth and duration specified by the manufacturer. Apple specifies “maximum depth of 6 meters up to 30 minutes”.