Dock & Menu Bar > Clock > Announce the time

This would seem to indicate a System Wide issue and is generally some piece of Their Party Software and or Kernel Extensions installed.

Suggest downloading the Application Etrecheck directly from a well Respected ASC Contributor. And Safe to use.

The application is free or paid from added features. 

Run the application with Full Disc Access ( Security & Privacy - Full Disc Access ).

It will take a Snap Shot -  both the hardware and software.

 The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - using the Additional Text Icon ( 3rd Icon to last )

We can have a look at the report for possible issues and may have possible suggestions to resolve the issues.

Thank you the Etrecheck Report

MacBook Pro (16-inch, 2021)

MacBook Pro Model: MacBookPro18,1

Apple M1 Pro (m1) CPU: 10-core

Major Issues:

Q - No Time Machine backup - Time Machine backup not found.

A - Not protecting ones’ impotent personal files gives the impression the Data Is Not Really Important at all.

Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS. F

Q - Unsigned files - There are unsigned software files installed. These files could be old, incompatible, and cause problems. They should be reviewed.

A -  Self explanatory 

Q - Kernel extensions present - This computer has kernel extensions that may not work in the future.

A - Refer to below regarding ESET

Q - iCloud Status: 4 pending files

A - refer to below regrind ESET

Q - Antivirus software: Apple and ESET Search - Apple Community

There are no known Windows-like Viruses in the wild that self replicate and affect macOS, because of the underling UNIX  Foundation and Permission Limitation. 

The Only thing this Antivirus software is protecting is the Bank Account of the Developers and for zero return to the User aside from the problems this software creates.

The The Built in Security  is all that is required to protect the computer.

Any Third Party Applications that will interfere with the normal operation of the OS, alter, modify, remove or delete or attempt to do so is an invitation for disaster and comprising the Operating System

Any of the below should be removed as per Developers Instructions 

Search - Apple Community - there are 196 posting regarding this application going all the way back to about El Capitan

There has been advise / suggestions offered for the User to make an informed and educated choice what the next course of action is required.

The suggestions have been put forth on a volunteer basis, in good faith and in the best interests of the computer.

Per chance and hopefully not but did the User ( you ) use Migration Assist after the Clean Installation ?

If so, Issues that may have existed on the Time Machine Backup when it was performed, may have been re-introduced into the Pristine and Virginal Installation.

Thusly, negating the hard work you have done with an Erase and Reinstallation.

1 - There could be something in the main User Account playing up. To further isolate this - Set up users, guests, and groups on Mac. Then log out of the Main User account and log into the dummy account and test again if the issue persists.

2 - If the issue is present in the dummy account - then, this appears to be a System Wide issue on the computer.

3 - If after performing each of the above steps is the order that have been presents  and still have issues - please advise for possible further assistance.

1 - Suggest restarting in Safe Mode. This will perform a Disk Repair, clear cache files and only load Apple Software, extensions and fonts. The boot up will be slow and can take some time - Normal.

2 - Does the issue present in this mode ?

3 - Sometimes a Safe Boot followed by a Normal Boot will just put things right.

4 - If not - there could be something in the main User Account playing up. To further isolate this - Set up users, guests, and groups on Mac. Then log out of the Main User account and log into the dummy account and test again if the issue persists.

5 - If the issue is present in the dummy account - then, this appears to be a System Wide issue on the computer.

6 - If after performing each of the above steps is the order that have been presents  and still have issues - please advise for possible further assistance.

7- Suggest downloading the Application Etrecheck directly from a well Respected ASC Contributor. And Safe to use.

The application is free or paid from added features. 

Run the application with Full Disc Access ( Security & Privacy - Full Disc Access ).

It will take a Snap Shot -  both the hardware and software.

 The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - using the Additional Text Icon ( 3rd Icon to last )

We can have a look at the report for possible issues and may have possible suggestions to resolve the issues.

Thank you and unfortunately the outcome remains the same.

Have personally never used this feature ever on any version of OS X or macOS since OS X 10.14 Tiger.

So, can not speak to this issue beyond what is supposed to work versus what accurately works in real life ( which it apples does not )

Based upon your experience and the added insights of a learned Contributors's ( @dialabrain ) it appears reasonable to conclude it does not work.

Product Feedback - Apple worth submitting a Bug Report directly to Apple wth as much details as possible

Just to let you know that you are not alone with this problem.

This feature has been broken (for me) for a long time.

It also stops working following a Logout Login.

FWIW, "Announce The Time" has not worked for me reliably since Catalina.

Welcome