[ldarby]

I'd assume that this listening functionality only comes with certain apps, that's certainly the case for ultrasonic tracking apps [0]. Probably you have just managed to avoid installing such apps.

[0] https://en.wikipedia.org/wiki/Cross-device_tracking#Applicat...

[fxd123]

The operating system shows when the microphone is turned on.

[g-b-r]

Only since Android 12