Can't read Time Machine backup with APFS case-sensitive format on Catalina

Question

So I took a Time Machine backup of a Mac running Big Sur, and the backup drive format defaulted to APFS (case-sensitive).

Now I am trying to read this backup from another Mac running Catalina (cannot update for various reasons) and the Time Machine just shows blank and I cannot access the data. I know the data is there because I am able to see it when I connect the backup drive on my sister's Mac (running Big Sur).

How do I read the data on the Mac with Catalina? Does Catalina not support APFS case-sensitive?

Trying to avoid having to copy all the data to my sister's laptop and then reformat the external drive and copy it again.

Answer 1

As noted here you can't access the Time Machine backup from your Big Sur machine on Catalina:

Not only must you use Big Sur to back up to an APFS-formatted Time Machine volume, you can’t even access the backups from a Mac with Catalina or an earlier macOS version installed.

You will have to bring a newer os to your existing machine to temporarily boot it, upgrade (which you expressed a preference to not do) or bring the data to another machine to move it.