iMessage, FaceTime, Focus Mode sync not working since iOS 17.1 update

Since I updated my iPhone 12 Pro from iOS 17 -> 17.1 I experience various service issues:

• iMessage won't activate. iMessage doesn't show the email addresses that are listed under iCloud settings
• FaceTime won't activate
• Focus modes don't sync with my MacBook Pro 2021 (Sonoma)
• Find my works but is very slow

My hypothesis is this is all service or identity related, some problem communicating with Apple services. I do have a VPN, but with that disabled there's no change in behavior.

I'm wondering if others experience these issues as well...