Comments on Emails are a huge time saver.
Labels are good for general actions llike 'Do' 'Await response', 'Read' 'Decide'
Comments are good when you have numerous emails from one sender all with same header.
If one of those emails needs to be found later there are a lot to sift through.
One email with a unique comment saves a lot of time.Eg 'Decision re meeting time' or 'Pay bill by 9Feb26'