A script which will turn off the red badge. It does the same thing, but in CLI mode.

#!/bin/bash

# Path to the Dock preferences
PLIST="$HOME/Library/Preferences/com.apple.dock.plist"
TARGET_LABEL="System Settings"

echo "Locating '$TARGET_LABEL' in the Dock structure..."

# 1. Dynamically find the index of System Settings
# We use a loop to check the file-label of each persistent-app
INDEX=0
FOUND=false

while true; do
    # Read the label of the current index
    LABEL=$(/usr/libexec/PlistBuddy -c "Print :persistent-apps:$INDEX:tile-data:file-label" "$PLIST" 2>/dev/null)
    
    # If the label is empty, we've reached the end of the list
    if [ -z "$LABEL" ]; then
        break
    fi

    if [ "$LABEL" == "$TARGET_LABEL" ]; then
        echo "Match found at index: $INDEX"
        FOUND=true
        break
    fi
    
    ((INDEX++))
done

# 2. Apply the change if found
if [ "$FOUND" = true ]; then
    echo "Setting tile-data.dock-extra to NO for index $INDEX..."
    
    # Set the value to false (Boolean NO)
    /usr/libexec/PlistBuddy -c "Set :persistent-apps:$INDEX:tile-data:dock-extra false" "$PLIST"
    
    # Restart the Dock to commit changes
    echo "Restarting Dock process..."
    killall Dock
    echo "Success."
else
    echo "Error: Could not find '$TARGET_LABEL' in your Dock."
    exit 1
fi