Without re-reading all of the above posts, have you found the following (posted on MacInTouch) to be the case:
"Mike Bombich, whose company makes Carbon Copy Cloner has stated in this podcast… that external backup drives in Catalina can no longer be HFS+ but must become APFS."
And does it really matter, or in what cases would it matter?
On a Mac since 1984.
Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
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