I've downloaded and installed the Network Link Conditioner for Xcode 13 from her https://developer.apple.com/download/more/?q=Additional%20Tools.
But it does not start instead it shows a generic error "Could not load Network Link Conditioner preference pane."
I tried to start it from a Terminal. There error I saw there
points me to the conclusion that it is not build M1 Mac.
I'm on Big Sur 11.6 with Xcode 13.0.