I'd say Apple is partially to blame for the replacement parts market being shady, for three reasons:
1. You can't get genuine Apple replacement parts in such a way that the end-consumer can actually verify they are not counterfeits.
2. Apple charges an exorbitant brand premium for genuine Apple products.
3. Apple doesn't believe that unapproved persons are capable of repairing its devices correctly.
If one could order a replacement battery from Apple, at a price that approaches the actual cost of a genuine replacement battery, plus the actual cost of QA, plus the actual cost of splitting off single units from the batch and shipping them, most would never need to bother with sketchy third-party batteries. You could just buy an Apple battery, and either DIY replace it, or take it to an electronics repair-person that you trust.
So it is Apple making things bad. By refusing to recognize consumer right to repair at all, it is automatically excluding the possibility that there is a difference between a shoddy home-repair, and one that would otherwise meet Apple's repair standards, if only it had been performed by an Apple-blessed individual.
A shop that values its reputation would almost certainly offer customers the choice of OEM-original replacement parts, or brands known by them to be good, such as iFixit parts, if it could. As it is now, the only OEM-originals they can get, come from devices purchased new for the explicit purpose of dissassembly for parts, and broken, unrepairable devices that still have some good parts in them. That pushes the prices up.
Batteries fail on a predictable schedule. You can either design your whole battery-powered product to fail roughly when the intrinsic battery fails, or you can design the battery to be replaceable.
Apple is trying to have the cake, by designing a product with a longer except-for-the-battery service life, and eat it too, by making the battery intrinsic to the construction, and not easily replaceable. These are incompatible goals for product lifecycle. Either you make cheap garbage that may break before the battery fails, or you have to account for repairing or replacing a failed battery in a product you have not owned in any way ever since you sold it to the consumer.
The consumer-friendly way to go about this would be to offer OEM-blessed battery replacements by sanctioned professionals AND sell repair parts directly to anyone who wants to buy them AND publish specifications for 3rd-party replacement batteries AND publish instructions on how to replace the battery AND write your software to detect and report incorrect installation or out-of-spec replacement parts, while also actually accepting any repair done correctly with in-spec parts without complaint.
The "issue" is that the current software is essentially saying, "we know everyone in the world who can properly replace an Apple battery, and whoever it was that replaced this battery wasn't one of them". Rather than offload the cost of their brand protection scheme onto the consumers, they could write their word trademark and mfg date to the chip in the battery, read it from the phone to report as part of battery health, and prosecute battery-counterfeiters in civil court, on their own dime, rather than using some bullshit para-DRM scheme.
Your ‘consumer friendly’ solution seems like just the opposite.
Your propose a costly scheme that would require significant ongoing investments in engineering and bureaucracy to maintain in order to support a network of less reliable repair shops policed by a never ending cycle of offensive lawsuits.
Not only would that not protect the brand, but it would harm consumers through increased pricing, and harm the repair shops by targeting them with lawsuits.
How can this possibly be better than the current situation where people are free to repair the device and use whatever batteries they like, and there are no lawsuits - only a message on a screen buried in the settings app!
1. You can't get genuine Apple replacement parts in such a way that the end-consumer can actually verify they are not counterfeits.
2. Apple charges an exorbitant brand premium for genuine Apple products.
3. Apple doesn't believe that unapproved persons are capable of repairing its devices correctly.
If one could order a replacement battery from Apple, at a price that approaches the actual cost of a genuine replacement battery, plus the actual cost of QA, plus the actual cost of splitting off single units from the batch and shipping them, most would never need to bother with sketchy third-party batteries. You could just buy an Apple battery, and either DIY replace it, or take it to an electronics repair-person that you trust.
So it is Apple making things bad. By refusing to recognize consumer right to repair at all, it is automatically excluding the possibility that there is a difference between a shoddy home-repair, and one that would otherwise meet Apple's repair standards, if only it had been performed by an Apple-blessed individual.
A shop that values its reputation would almost certainly offer customers the choice of OEM-original replacement parts, or brands known by them to be good, such as iFixit parts, if it could. As it is now, the only OEM-originals they can get, come from devices purchased new for the explicit purpose of dissassembly for parts, and broken, unrepairable devices that still have some good parts in them. That pushes the prices up.