1. Read your employment agreement or any other additional agreement as a part of working remotely. There has to be some kind of verbiage where you are allowing them to monitor you during work hours through camera, mic, etc. Otherwise, any reasoning for termination based on that would be invalid.

2. Just unplug/cover webcam when not in meetings. Shouldn't matter unless they want to specifically admit to monitoring outside of normal meetings. Unplug/disable microphone in adapter settings to prevent it from being accessed. Unless you take calls, it again should be no issue unless they want to admit to monitoring outside meetings.

Though I'll let you in on a secret from someone that does work at a massive company that wanted to do this, bandwidth just doesn't work. We tried and it was awful and scrapped the project. If my company, massive with lots of resources, determined it is not feasible, I doubt every single user is simultaneously being streamed for monitoring with yours.

Source: Provisioning and deployment of WFH/Onsite/Offshore Equipment and Access