From the article:
"T-Mobile does not currently collect app data on iOS users, fearing it could run afoul of Apple's privacy rules. ...you can opt-out of T-Mobile's program using its official "Magenta Marketing Platform Choices" app."
"T-Mobile does not currently collect app data on iOS users, fearing it could run afoul of Apple's privacy rules. ...you can opt-out of T-Mobile's program using its official "Magenta Marketing Platform Choices" app."
Their motivation seems to be to gradually reduce in size, and eventually eliminate SIM cards - presumably just to free up internal volume. But they've been successful in forcing MNOs to do that anyway.