If you disable the "camera access" using the quick setting toggle, the microphone also gets disabled/muted. As a result, all apps requiring the microphone (assistant, phone, recorder, etc) stop working properly. The microphone seems indeed enabled (no warning about it being disabled) but not recording any sound whatsoever.
I've attached a screen capture of using the recorder app (while music is being played aloud) and disabling the camera while recording. Notice how the microphone quick setting remains enabled.
Honestly, the amount (and seriousness) of bugs on this phone is getting ridiculous...
Model name: Zenfone 9 (128gb)
Firmware version: WW_33.0804.2060.100