That is true that would solve things temporarily but once you need to download a new app or would like to purchase music for example, then you would have to sign back in and the problem would reoccur.
I just got off the phone with Apple tech-support. Yes things are working correctly. Any and all devices with the same Apple ID/iCloud account will have all phone logs and voicemails merged. Tech told me that you should only be able to answer phone calls on the soul device though.
Tech confirm that it is due to the upgrade in the iOS 17. Things are working correctly and this is how it should’ve worked from the beginning. But Apple made a loophole where if you turned off phone in iCloud then it would not merge this information.
Yes for people wondering, I do have everything set correctly. I have call forwarding off I have handoff shut off. I have phone toggle off on iCloud. I have phones set to receive calls at their current number along with text and FaceTime calls.
To make the story short, every device must have their own Apple ID/iCloud.
I asked tech-support if I deactivated and deleted iCloud would it stop doing it then they said it would but then I would not be able to download new apps, manage subscriptions, purchase new music, or do anything that required my Apple ID/iCloud account.
When I spoke to Apple support, I told em the long story that I have had an apple iPhone forever and I have shared an apple ID with both my parents since I can remember. Long before family sharing existed. I am 33 so if you do the math I have had an iPhone for almost two decades and I have shared an Apple ID for 14+ years with my parents. I never created them their own Apple ID, because they never had their own email. For convenience purposes, this continued so I can track them and share certain things I wanted to share with them. Then Apple support offered to help me create them their own Apple ID through family sharing. Although this would help. My parents moved one year ago to another state. In order to have this done I would have to fly to them and log off my own Apple ID and set them up with their own. If I choose to do this through screen sharing it would literally take hours.