I just upgraded to windows 11 beta and it doesnt have a clock in the task bar when using multiple monitors. This is a simple clock that shows up on the bottom right corner of all additional screens (only tested with 2 but technically should work on more)

You can exit the clock from the context menu if you right click on the time/date text (make sure to point at the text not the blank space)

There are no options or any interface elements other than the clock itself but I can add more options if requested

There are 2 pre-built binaries available

• A self contained clickonce setup (250mb)
• An executable only version that requires .net 6 (87kb)

you can follow the instructions in this guide https://support.microsoft.com/en-us/windows/add-an-app-to-run-automatically-at-startup-in-windows-10-150da165-dcd9-7230-517b-cf3c295d89dd