Migrating to my new Mac using Carbon Copy Cloner

It is not possible to completely migrate your old Mac solely using Carbon Copy Cloner. The following if from the developer:

You should not restore a backup of macOS System files from one Mac to another. While this has worked in the past, Apple has made it clear that this is no longer supported. You may restore data from one Mac to another — use Migration Assistant to migrate data from your CCC backup to another Mac.

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When you get a new computer from Apple, it has a specific version of macOS installed on it, and further, a hardware-specific "build". Your new Macintosh cannot boot from the older version and build of macOS that is installed on your older Mac, so simply restoring your old Mac's backup onto your new Mac won't work. We recommend that you use the Setup Assistant application (runs on your Mac's very first boot) or the Migration Assistant application to migrate content from your old Mac to a new Macintosh. You can migrate directly from a CCC backup of your old Mac. Once you have migrated your user accounts and applications using Setup Assistant or Migration Assistant, you can continue to use CCC to back up your Mac to the same backup volume that you were using for the old Mac.