What is the model?
I was thinking of smth like that years ago, even as a physical add-on like smth to glue-on. I found nothing like that for thinkpads nor macbooks
A webcam can easily be 'disabled' with some tape. I'm more worried about someone enabling the microphone (harder to disable internally)
Can't you bypass the built-in mic by plugging something in the mic jack, like spare earbuds, or just a connector cut from some old or broken mic, headphone or spekear?
What about macbooks all-in-one headphones and mic port?
What about smartphone/tablet cameras and mics?
but it could leave glue on the lenses. Tape is not always what you want to have in front of your laptop