Numerous iOS apps are using background processes triggered by push notifications to collect user data about devices, potentially allowing the creation of fingerprinting profiles used for tracking.
And to advertise their bullshit deals to keep you spending. Uber is a big one, Best Buy is another. Push notifications should have an option to opt out of spam notifications. They shouldn’t even be a thing.
Yeah, there should be fine grained options (e.g. "marketing") in the settings, or at the very least an opt-out toggle, where use of the wrong channel is against TOS and results in delisting from the app store.
Finer grained control is needed regardless — enabling apps and users to control critical and regular notifications based on each individual use case.
There should also be a notification log on the device, that shows you all associated information — many apps will offer something via notification that is not available to you, which is considered false advertising and is illegal in my country. This should also breach TOS. There are also many errors where the notification links to nowhere. Once you click the notification, it's gone forever, which is a horrifically bad design decision.