I was able to follow these steps and it does say to wait 24 hours for propagation and hopefully I'll go back to deleting the identifier again: https://help.apple.com/app-store-connect/#/dev7013b314c

Although the "Remove" button is visible to invalidate this App ID, I receive "There is a problem with the request entity: The App ID 'SJAV7HZQZ6.com.XXX.XYZ' appears to be in use by the App Store, so it can not be removed at this time."