Like others I use copy software (Super Duper) to copy to on-site drives, have a Time Machine drive just because I can and off site back-up to iDrive.
I use to have at least one full clone of the boot disk kept totally up to date very easily by Super Duper. I really liked this and it had saved me a few times over the years from "updating" (and other) mis-adventures.
However, since Mac OS "Catalina", Apple has divided the bootable (now "read only") system drive to a separate drive partition from the data partition of that physical drive. You can see this in "Disk Utility" (but not usually in the "Finder"). This caused the clone software (Super Duper) to initially have issues (I think Carbon Copy had them also). Eventually Super Duper was updated to make a bootable clone but it is not the same as the earlier versions in that incremental backups ("Smart Copy" in Super Duper terms) are really just to the Data partition. (It use to be that "Smart Copy" incremental backups would make the entire drive a bootable, updated clone of the system drive)
To make the system "read only" partition up to date, at least at the present time, the entire cloned, bootable disk has to be fully erased then recopied ("Erase and Copy" in Super Duper terms). After it is made, the bootable drive does seem to work but, how much it all resembles the original startup drive's operating system looks to depend on how often it was erased and recopied.
For major upgrade trials (i.e. going from Monterey to Ventura) it is good to use the Mac OS feature that will make an install drive of the current Mac OS just in case the new OS is a bit too full of fun "features" causing a desire to revert backwards.