This worked for me: I removed the command line tools as root and reinstalled …
Your Command Line Tools (CLT) does not support macOS 11.
It is either outdated or was modified.
Please update your Command Line Tools (CLT) or delete it if no updates are available.
Update them from Software Update in System Preferences or run:
softwareupdate --all --install --force
If that doesn’t show you any updates, run:
sudo rm -rf /Library/Developer/CommandLineTools
sudo xcode-select --install
Alternatively, manually download them from:
https://developer.apple.com/download/more/.