pdxGuy1959

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PERockwell said:

Mike made a blog post about this over 3 years ago t https://bombich.com/blog/2021/05/19/beyond-bootable-backups-adapting-recovery-strategies-evolving-platform).  
A significant quote from that blog:

Back in December I had a conference call with Apple about the reliability and functionality of ASR on macOS and regarding Apple Silicon Macs in particular. They indicated that they were working to resolve the ASR/Apple Fabric issue, but they made it very clear that copying macOS system files was not something that would be supportable in the future. Many of us in the Mac community could see that this was the direction Apple was moving, and now we finally have confirmation. Especially since the introduction of APFS, Apple has been moving towards a lockdown of macOS system files, sacrificing some convenience for increased security.

If you've done your research, you can find that bootable external disks can still be made, but your best method of doing so (recommended by a number of sources) is to create a data-volume only duplicate to the external disk, then perform a macOS installation to the external disk.  See Install macOS on an external storage device and use it as a startup disk and make-a-ventura-bootable-external-disk-for-an-apple-silicon-mac ...

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Mike Bombich updated his older post, as of 12/19, with a new Blog comment on this topic...

https://bombich.com/blog/2024/12/19/bootable-backups-have-been-deprecated-for-several-years