PlistWatch monitors real-time changes to plist files on your system.
It outputs a defaults command to recreate that change.
go install github.com/catilac/plistwatch@latest
Just run:
plistwatch
Now make some changes, such as moving the Dock and moving it back by clicking the Position of Screen options. You should see the changes being reported. You may also see other events being reported.
And you should see output such as:
defaults write "com.apple.dock" "orientation" 'left'