The direction where all this is developing is genuinely concerning. So all of a sudden 3rd-party apps must enjoy "the same hardware and software features" available to the OS? Siri can carry out actions for a user in a hands-free fashion using SiriKit and App Intent architecture, so does that mean Apple must grant any random app the same privileges? I don't want X to decide to peek into my photos library for political memes in the middle of the night and I believe no one would want that.
Siri also support activation by certain "magic words", like "Hey Siri", and this is done securely (so that the iPhone isn't actively listening 24/7) thanks to a clever software implementation and the involvement of Secure Enclave. Apple has long documented these extensively in their
Platform Security Guide. Are 3rd-party apps going to access Secure Enclave as well? The Enclave is locked down even from the main processor, and that is the whole point (so that it can not be compromised even if the main processor is)!
Even if Apple could expose all these functionalities via new system APIs (which is already a security compromise because now these mechanisms is no longer sealed in the OS), due to the immense potential power of these APIs, apps will ideally have to undergo detailed scrutiny to be allowed to use them to make sure they are not using the APIs for malicious purposes. Well, guess what, the EU mandates third-party app stores! Dear EU, can you make sure each of these stores also review apps carefully, or at least in the same level as Apple's?
One can see why Apple has to, tragically, block certain features in EU just to satisfy those regulators who don't understand nor care how tech works. It is trying to avoid being forced into opening new attack surfaces and compromising the security model. I am glad I don't live in the EU but unfortunately, not understanding how the tech works, regulators in other countries are likely to follow. This is bad news for all those tho care about privacy and security of their devices.
EU regulators, you can't put Canon's ink into Epson printers. And good luck trying to force a Ford engine into a Toyota.