Why can't Outlook users edit the subject line of incoming emails?

@Don Varnau thanks for the tip and was really hoping this was going to be a viable work around, although why we're even having this discussion is utterly ridiculous..... Change for the sake of change while not adding any user benefit and instead removing a vital feature is purely job security for these companies. I am so over every new update where nothing is where it used to be or its buried 4 steps even further down some rabbit hole and makes everything more difficult and you loose features has really gotten out of hand..... So, in your case with this tip, when I open an email in Notepad from the desktop, it just comes up all garbled and no way to find the subject line or attempt any modifications. Am I missing a step or ???Here's what it looks like: À F ç—UþÇÚ
 €a _ _ n a m e i d _ v e r s i o n 1 . 0 (

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_ _ s [snip]_ - - - Sorry. You're right. It does not work for me with Outlook 2016. I've edited my post. Don

@Don Varnau thanks for the tip and was really hoping this was going to be a viable work around, although why we're even having this discussion is utterly ridiculous..... Change for the sake of change while not adding any user benefit and instead removing a vital feature is purely job security for these companies. I am so over every new update where nothing is where it used to be or its buried 4 steps even further down some rabbit hole and makes everything more difficult and you loose features has really gotten out of hand..... So, in your case with this tip, when I open an email in Notepad from the desktop, it just comes up all garbled and no way to find the subject line or attempt any modifications. Am I missing a step or ???Here's what it looks like: À F ç—UþÇÚ
 €a _ _ n a m e i d _ v e r s i o n 1 . 0 (

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ЋUþÇÚ
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This is a VERY big inconvenience for me. When I receive an email there could be a couple of things I'm waiting on or someone. I'll type on the subject line Who and/or What I'm waiting on. This can't be flagged. I need to Type on the Subject line so I know what and/or who I'm waiting on.

It would appear not; and it is VERY ANNOYING!!

Hello, since June 2023 I am using Office 365 (Legacy Outlook) on a MAC. The past few months, I could change the subject of an received e-mail. Suddenly today I can’t. The e-mail subject will be changed to the originally subject after a few seconds. Is there somehow this can be changed by to yesterday?

Best regards, Kevin