Is there no way to transfer time machine backups from a failing disk with Monterey?

I do agree with you that the ability to "clone" an existing backup drive would be nice to have. I used to do this in years past. I think the ability to do some simple things like this has been lost, in return for the many other improvements that have been brought to computers in the last several years.

I think the vast majority of users who do make backups use Time Machine on one external drive. When that one external drive shows signs of failure, they throw it away and start in with a new backup drive. They don't worry about it or think about it more than that. They don't worry about any "time history" kept by Time Machine that they lose in the short term -- how far back that time history goes is variable and not something one can count on anyway. Many others simply have their files in the cloud and don't even bother with local backups.

I work on spacecraft systems that need to be space qualified and we have a rigorous approach to reliability and redundancy. We keep multiple backups of all critical flight and ground software. I can't help but be influenced by what I deal with all day long so that carries over into my personal storage and backup approach. Maybe a bit over the top, but it has paid off when we suddenly have a failure of some sort.

Back to your practical issue -- keep in mind that failing drives will sometimes but not always fail the file system check (fsck) which does not actually check the drive physical health, but rather checks the file system. A drive with marginal or intermittent physical defects may be ok for some of these fsck checks but not for others. The more a marginal drive is exercised the more likely it is to fail. So I would start in with one (or more) new Time Machine backups (plus add other types of backups) and keep (not using it anymore) the old backup drive as archive "just in case" you need an older file. After some months go by, you will have accumulated a new Time Machine "history" with the new backups.

I agree it would be nice to be able to simply clone or copy backup drives but that no longer works with the snapshot methods used by the MacOS. It is not optimal but it is a constraint we have to accept, I don't see this capability coming back any time soon.

It has never been desirable to copy a backup drive to another backup drive, and copying anything from a device that is known to be operating in a state of failure is ill-advised.

Furthermore, it is no longer possible. The only justifiable reason to copy a TM backup from one drive to another in past TM versions was when the user decided a backup drive's capacity is not longer sufficient.

All drives fail eventually.

Which is the reason that one and only one backup device does not comprise a robust backup strategy.

Even if you use the 2 disk method from the get-go, both drives may fail.

Simultaneously? Not likely, but two drives in the same physical proximity of one another can easily become lost in a catastrophic event. That is the reason that three or more backup drives, with one kept geographically separate from the other two at all times, is close to ideal.

Superduper offers some copying of time machine backups to hard drives that are similarly formatted. So you can't copy from an HFS Extended to an APFS.

The Finder does too, but you will not be able to import the data into the Time Machine to view past records in the elegant method Time Machine has of viewing past folders.

If the hard drive is functional that has the Time Machine backup, you can use the MIgration/Setup Assistant in Applications -> Utilities, or on setting up a newly installed OS on a new drive to import the data to another drive. Obviously it would have to be the same or newer OS that imports it, and have to have the space to import the whole backup.

What is the point of retaining months or years of backups at all if they are never useful?

Time Machine does not “retain months or years of backups.” It is not archival. It will eventually remove items you have deleted from your Mac. While it will retain deleted items for quite some time depending on drive space. You should never assume it contains anything more than a current duplicate of your drive.

If you want to ensure you “retain months or years of backups,” you must pull the drive from the rotation before it fills and stow it away. Copying and continuing the backup on a larger drive might extend the time they are available.

To avoid the problem of a failing drive, you create two or three backups. You could choose an archival backup as the other two methods.

Presumably, I could transfer all of the data to a new disk, except that Apple protocols inexplicably block me from doing so, for arbitrary design reasons, for the first time since Time Machine was created.

Since you know Apple's reasons are arbitrary, you should tell them: Product Feedback - Apple. They may not be aware of that fact.

1) The current disk is failing ...

Throw it out. Full stop.

... and you want to retain that complete history.

Already accomplished with redundant backup disks.

2) The current disk is small and you want to continue the full history on a larger drive.

Put it on the shelf, where its backup history will remain accessible for as long as you want to retain it, but more about that later.

3) You want to archive the current backups for a backup of backups, for data safety reasons.

You never want to "backup a backup". That's ill-advised. Multiple redundant backups are not "backups of backups". They are redundant — which is what any effective and robust backup strategy requires.

Time Machine guarantees a minimum of one and only one complete and restorable backup. That's it. Any more than that is "nice to have" but not guaranteed.

With the recognition that everyone's backup needs are different, the likelihood of having to restore an item that was backed up months ago diminishes with the passage time. You may be more interested in an archival system, which Time Machine is not, and was never designed to implement.

I routinely erase backup disks after they accumulate about a year's worth of backups. I should probably do it more often than that.

But I am hoping that Apple will see the need and restore this lost and very useful capability.

Don't hold your breath.

Is Apple planning to provide an easy, visible, and intuitive method to meet this urgent need?

Nobody here could possibly know what Apple plans to do.

There is no way to copy a Time Machine backup. There is no way to clone a Time Machine backup.

It has nothing to do with Monterey itself. Time Machine now uses an APFS Snapshot methodology which cannot be copied.

tunesmith82 wrote:

It seems really absurd not to have any method to move backups from a failing drive to a new drive. All drives fail eventually. Even if you use the 2 disk method from the get-go, both drives may fail. Surely, Apple realizes this.

Making a copy of an existing backup does not create a redundant backup, since the copy contains any and all of the flaws in the first backup media. The fact that your backup media is actually failing accentuates the logical flaw in your approach here. Making a copy might leave you with a copy of ... something that is failing.

The right approach is to alternate between two (or even three) Time Machine backups from the get go so if one fails you still have the same (limited) "history." For a real archive, you would need to run a clone type backup at regular intervals and archive those (examples include CCC, SuperDuper, plus other similarly capable programs) periodically, since eventually Time Machine backups do delete older backups. Or purchase a backup program that properly and truly archives. Having more than one method of backup and also storing at least one type off site adds more resiliency.

Making a copy of something that is already malfunctioning does not seem resilient to me. Yes, it would be nice to be able to do, as a last gasp effort, but the mechanics of doing this have been overtaken by the snapshot method used by the MacOS and I speculate that it was not cost effective for Apple to maintain ability to copy backups given that probably only a small fraction of its customers would want to do this.

Get the new disk and create a new TM backup on it. No transferring, cloning or copying needed.