In https://developer.apple.com/forums/thread/650369 I see that the softwareudpate --ignore flag deprecated in Big Sur and above.
So now I get offered four versions of the Command Line Tools by Big Sur:
Software Update found the following new or updated software:
Label: Command Line Tools for Xcode-12.4
Title: Command Line Tools for Xcode, Version: 12.4, Size: 440392K, Recommended: YES,
Label: Command Line Tools for Xcode-13.2
Title: Command Line Tools for Xcode, Version: 13.2, Size: 577329K, Recommended: YES,
Label: Command Line Tools for Xcode-12.5
Title: Command Line Tools for Xcode, Version: 12.5, Size: 470966K, Recommended: YES,
Label: Command Line Tools for Xcode-12.5
Title: Command Line Tools for Xcode, Version: 12.5, Size: 470820K, Recommended: YES,
I no longer can hide/get rid of those for Xcode 12.x. This is not good!
P.S. I installed "Command Line Tools for Xcode-13.2" twice, but softwareudpate is still showing it as available.