A good life hack I figured out is to smear your laptop camera and microphone with sticky tack, not to totally disable them but to insufferably degrade them, then after a few attempts you can be excused from the expectation of ever appearing on video calls and can disable both permanently.

If you start by hitting backspace a few times and/or typing random characters and deleting them (to make sure the keyboard's working and sending your inputs where you think) it should obscure the length somewhat.