I'm another with this issue using Windows 11 that never happened with Windows 10 (or earlier versions, going back to the heady days of Windows 3.1 Service Pack 1). This is not a semantics issue, it's a Windows 11 and/or RealTek one... My headset mic did work for a *while* with the headset plugged in, until one day it stopped (even with a second headset, and a second laptop running Windows 11). A full restart would sometimes rectify it, sometimes not. There is clearly an incompatibility with RealTek and some other audio software piece added to Windows 11, and/or hibernation mode in a Laptop. My RealTek audio driver is up today. Windows troubleshooting is useless.
It's definetely a bug to do when plugging/unplugging the headset between Windows restarts (or without a full restart), and more likely, when the Laptop (in my case), comes in/out of hibernation mode. In the hybrid working era, this issue should be viewed as Critical.
I've been a happy Windows user for 26 years, but the answers I have found here do not address the issue. I would not be surprised if the issue lay on RealTek's door, but it seems uninstalling the audio driver can cause bigger problems, so I'm not going to do that.
Why Microsoft would be happy to push such a critical failure out of the door seems ludricious to me. It shouldn't be too hard to get some QA trying different headsets in the jack until it repeats.