Apple uses Blind Signatures for attestation. It's how they avoid captchas at CloudFlare and Fastly in their Private Relay product
If I'm reading any of this correctly, this doesn't apply to hardware attestation.
It seems apple has a service, with an easily rotated key and an agreement with providers. If the key _Apple_ uses is compromised, they can rotate it.
BUT, apple knows _EXACTLY_ who I am. I attest to them using my hardware, they know _EXACTLY_ which hardware I'm using. They can ban me or my hardware. They then their centralized service gives me a blind token. But apple, may, still know exactly who owns which blind tokens.
However, I cannot generate blind tokens on my own. I _MUST_ talk to some centralized service that can I identify me. If that is not the case, then any single compromised device can generate infinite blind tokens rending all the tokens useless.
Yes, this has the side effect of making them more money and allowing a walled garden to form, but given that the vast majority of users wouldn't do anything different with their phones if a shell was present, this is in my opinion not that large of an effect.
The snide around "clicking on links is dangerous" and locking down the bootloader is unwarranted, because for most people a phone is not a toy (or at least, not just a toy) - it has their communications history, their bank information, their passwords, any many more. And it's really easy to steal people's phones on the subway. This isn't about freedom of computing, this is about the fact that an iPhone in BFU is nearly as secure as a GrapheneOS phone.
There are many problems with Apple software. It's buggy, uses proprietary formats that you can't export, and interoperable with open standards. It's bad, and is the primary reason why I won't buy another iPhone, but Macs have that same problem. On the other hand, being cryptographically locked-down is an optional feature. If you don't like it, buy a computer without that feature. It's harmful to us, to tinkerers and people who want to see how things work, but the average person does not care at all and just wants to be able to open LOVE-LETTER-FOR-YOU.TXT.vbs without having their 401k get drained.
You don't understand the argument of why people might want to install their own OS on a device they own. And then say you won't buy another iPhone because you don't like their software... It sounds like you _do_ understand the argument.
I greatly dislike Apple software, but I think their hardware is quite nice. I would buy apple hardware if it wasn't handy-caped by their OS.
It used to be said that Apple was a hardware company that happens to make an OS. This argument never made sense to me, because while they make good hardware they very clearly don't want people to use it.