I don't think it is possible to access Apple Intelligence / Siri features if you are using the beta having booted from an external SSD.

Would it be possible to trigger a background task such as updating a widget from a notification received from CKSyncEngine?

I had (mistakenly) set visibleRelationships to .current - will change to .all and report back. Many thanks for such a speedy response.

Glad I'm not alone, M1 Xcode 13b5 - crashes in 15.0 simulator, but not in: 14.7 simulator, or running in rosetta or building on physical device running 15.0 beta.