Local contacts only under Android 11?

I'm using Android 11 on my rooted Pixel 5 phone. It turns out that the Contacts app under this OS does not allow access of device-only contacts. I can only access contacts via a shared Google account. Furthermore, if I go to Settings and try to disable network permissions for the Contacts app, it turns out that the Permissions settings are greyed out, and I cannot alter any permissions for the Contacts app. I know that I can disable contacts sync-ing, but I want to go further. I want my contacts to be totally and completely disconnected from Google. I am happy to use an alternative contacts app that accesses device-only contacts, but that app would also have to be able to feed my contact information to all SMS and phone apps that I might use. Does anyone know how I can ... (1) ... go to Google and remove all my contacts there without this causing local contacts on my device to also be removed? (2) ... break all (!!!) connections between Google's cloud-based contact storage and my local, device-only contact storage. (3) ... reliably allow all device-only contacts to be available to other apps, including (but not limited to!) SMS apps and phone apps? I know I can manage this by switching from standard Android to something like microg. But I'm hoping that there is some way that I could still stick with Android 11 and have device-only contacts with no sharing with Google in any manner. I know that under Android, contacts are managed via a Contacts Provider service. Does anyone know of a way to disable the standard Android Contacts Provider service and somehow install some sort of alternate Contacts Provider service which would allow the use of device-only contacts and which could be configured to never, never, ***ever*** (!!!!!) share any contacts-related information with Google? Thank you in advance for any thoughts and suggestions.