This requirement that certain app functionalities may only be provided by Apple's own apps needs to be challenged in court via a class action suit so that they

This requirement that certain app functionalities may only be provided by Apple's own apps needs to be challenged in court via a class action suit so that they may be forced to unbundle these. These apps should be deletable and you should be able to programmatically assign their responsibilities to another application of your choosing. We've had this capability on the desktop forever. There is not pro-consumer argument Apple could make for denying a setting that lets you change this.