That is a useful distinction, and I’m not claiming Apple has shut down activation for all iOS 9 devices. My previous response specifically said that an actual discontinuation had not been established.
Taking your experiences as accurate, some devices can still activate while others cannot. That narrows the technical question, but it does not establish why the affected devices fail. Communication with a Mac, a response from a server, and successful completion of activation are different things.
More importantly, that does not establish the original legal claim, that a continuing iOS license obligates Apple to provide activation indefinitely, or requires Apple to upgrade, uninstall, back up, and unlock the device if it does not. Those obligations would need a contractual or applicable legal basis.
We can agree that hardware obsolescence does not itself terminate the software license, and that an activation failure deserves investigation, without concluding that the license guarantees perpetual activation support.
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