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In my view, this is just a very big middle finger of the customer.
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In fact it is, in addition to a disguised monopoly. Since you have to use original parts and associate serial numbers, you exclude third parties.
In the long past there was a debate with cars about whether or not you had your car repaired in the official garage. Ultimately, manufacturers are obligated to provide workshop manuals and your (legal) warranty does not expire if your maintenance is not performed in an official (branded) garage (and rightly so).

The reason is this principle:
If you assume that the manufacturer is only fit to do the repair themselves, you create a kind of monopoly and avoid competition, so there is no incentive to work cheaper/better.

Ultimately, you want what the manufacturer does to be in the customer’s best interest/benefit. In society, the customer, the person, is a superior commodity than the commercial organisations. do not forget it. You also do not want drugs to become unrealistically expensive, because profit.

She sees Apple stepping on her feet again and again.
iPhones cannot be expanded with SD cards. Not a problem per se, unless you find out that the additional internal storage is a factor that is 5~10% more expensive than SD cards. And speed is no excuse, as NVME SSDs are no more expensive in return.
Apple sticks with the Lightning connector. Not only that, they made the connector smaller a long time ago, so many people needed new (expensive) cables again.
Deleting the 3.5mm connection: Increases sales of wireless headphones.

And now this. Another development that leads to additional customer spending, but which is difficult to defend. And these things did not last for a year or two, but for five to ten years.
It’s a shame, because Apple makes very nice products. Apple’s update policy is usually arranged in contrast to Android. But practices like this keep me away from Apple. I don’t want to be deceptive, not directly or indirectly or in a suspicious way.
It’s like peeing in your pants when it’s cold. And after all these years, the smell can no longer be hidden…