apple time machine keeps destroying my external hard drives

Wow! Before going to such extremes, try running Disk Utility First Aid while booted in Recovery.

I saw very similar errors to the above, which did seem related to Time Machine having run, while running Big Sur 11.7.

Here's the scenario:

"Time Machine" is a single APFS volume on an external disk, with another identical single-volume APFS disk in the same enclosure; both sharing a TB2 cable to the MBP.  

TM had been set to run overnight every 4 days.  Perhaps because i don't routinely use the other drive, it wasn't until several days later I'd notice the non-TM drive was not mounted.  

Running Disk Utility from normal boot, the non-TM drive had an odd, vaguely-generic name.  (Once it was shown as Time Machine!)  DU First Aid gave similar errors as you showed above, and that one drive would not mount on re-boot.  "Time Machine" drive never had a problem.

Intending to re-format, I first ran Disk Util from Recovery and noticed it correctly reported the disk name, etc.  I then ran First Aid on the drive at all levels, which ran without error. After re-booting, that second drive also mounted correctly with it's normal name.

This happened maybe 5 times.  Since I knew the work-around, I wasn't too concerned.  I chalk it up to a software problem in the OS; rather do the work-around than run Apple's gauntlet.  I just installed Monterey, haven’t seen it… yet.

It is not attributable to a drive problem. DriveDX SMART reports no errors, other than the bogus shock events.

=== DRIVE ERROR LOG ===

error log is empty

=== DRIVE SELF-TEST LOG ===

#   | LIFETIME (H)   | TEST TYPE         | PROGRESS | STATUS                          | LBA of 1st error

1          4771        Extended offline       10%     Aborted by host                      -     

2          2368        Short offline         100%     Completed without error         -     

=== DEVICE STATISTICS ===

[0x01] General Statistics (revision 2)

  0x08 Lifetime Power-on Resets                  : 2,839 

  0x10 Power-on Hours                            : 5,079 hours

  0x18 Logical Sectors Written                   : 16,639,655,832 (8.5 TB)

  0x20 Number of Write Commands                  : 161,390,899 

  0x28 Logical Sectors Read                      : 7,548,700,803 (3.9 TB)

  0x30 Number of Read Commands                   : 276,177,607 

[0x02] Free Fall Statistics (revision 1)

  0x10 Overlimit Shock Events                    : 3  (bogus; it once incremented as I watched!!)

[0x03] Rotating Media Statistics (revision 1)

  0x08 Spindle Motor Power-on Hours              : 4,983 hours

  0x10 Head Flying Hours                         : 3,159 hours

  0x18 Head Loaded Events                        : 5,963 

  0x20 Reallocated Logical Sector Count          : 0 (0 B)

  0x28 Read Recovery Attempts                    : 0 

  0x30 Mechanical Start Failure Count            : 0 

[0x04] General Errors Statistics (revision 1)

  0x08 Number of Reported Uncorrectable Errors   : 0 

  0x10 Resets Between Cmd Accept. and Compl.     : 1 

[0x05] Temperature Statistics (revision 1)

  0x08 Current Temperature                       : 32 °C

  0x10 Average Short Term Temperature            : 33 °C

  0x18 Average Long Term Temperature             : 33 °C

  0x20 Highest Temperature                       : 45 °C

  0x28 Lowest Temperature                        : 16 °C

  0x30 Highest Avg. Short Term Temperature       : 41 °C

  0x38 Lowest Avg. Short Term Temperature        : 27 °C

  0x40 Highest Avg. Long Term Temperature        : 39 °C

  0x48 Lowest Avg. Long Term Temperature         : 30 °C

  0x50 Time in Over-Temperature                  : 0 minutes

  0x58 Specified Max Operating Temperature       : 55 °C

  0x60 Time in Under-Temperature                 : 0 minutes

0x68 Specified Min Operating Temperature       : 5 °C

[0x06] Transport Statistics (revision 1)

  0x08 Number of Hardware Resets                 : 10,754 

  0x18 Number of Interface CRC Errors            : 0 

________________________

There are no pervasive reports of drive issues that can be traced back to use with Time machine that have been posted here.

Drives have a limited lifespan, and rotating magnetic drives in particular are exceeding complex devices that are subject to arbitrary and captious errors for no particular reason. The most common end-of-life failure mechanism is when a drive accumulates a few errors, then a few more, then it snowballs into dozens, then hundreds, then unusable.

After erasing a drive that had errors, if it continues to cause problems, it is likely not good enough to hold you precious data any longer, and should be retired.

Time Machine does not use drives in an especially arduous way. But drives do get old and die, some long before their expected lifespan. Occasionally, the drive maker will replace a drive under warranty if it failed too soon.

You should have selected GUID partition Map.

if you did not, and selected the outdated Master Boot Record instead, Time machine may try to convert the drive to Apple File System (APFS) and that could fail, or the backup could later fail.

You may end up where you were before, with the disk unusable.

use the little View menu to choose Show all devices.

The select the PHYSICAL drive by its immutable manufacturer suppled name, and ERASE everything.

If that is not successful, immediately ask again (without leaving Disk Utility).

if it fails after that, then the drive itself may have failed.

Inspect the label on the drive. if the manufacturer's warranty still applies, return it to them for exchange.

please try my suggestion above.

the important step is selecting the ENTIRE physical device (Not just the Volume) and attempting to ERASE.

If that works or does not work, please let readers know.

Apple File system (APFS) is the latest File system, first widely used in 10.13 High Sierra. Seeing Time machine convert the drive from MacOS Extended to APFS is expected behavior.

What you need to have done to support that is to have used GUID partition Map (first widely used in MacOS 10.4 Leopard) when creating the Volume in the fist place, so that it does not make mistakes.

How exactly were multiple drives "destroyed"? How were they formatted before APFS?

https://www.minitool.com/data-recovery/apfs-vs-mac-os-extended-difference-and-format.html

what message do you get when you click ERASE.

<< "unrepairable" >>

what do you mean by that, exactly?

So you say that you cannot erase those disks?