Apps on your PC can't detect and use the microphone if you've inadvertently disabled its access via the Windows 11 privacy ...

This post will show you how to allow or disallow App permissions in Windows 11/10 ... can choose which apps have access and which don’t. The Allows access to the microphone on this device ...

One of the smarter things Microsoft did with Windows ... you can choose to allow apps to use a Microphone, i.e., listen in the background, and also choose which app has access to it.