In the WWDC presentation, a "guest key" was mentioned, but only in relation to watchOS. Are there any more details about that somewhere? I can't find it on the developer documentation for either Home or Wallet. https://9to5mac.com/2026/06/09/top-watchos-27-features-that-will-enhance-your-apple-watch/

I'm curious as to the rationale as to why Japanese IDs are not allowed on wearOS, even though American ones are.