Managing sound and video settings during Teams meetings and calls for optimal communication
Apparently this is a problem with Intel based Macbooks and is not a problem with the M1 Macbooks (different driver?).
The suggestion was made to me to run Teams in PWA mode (inside a web browser) rather than the native app. That does work. The jittery video was not present. Unfortunately the Web-based mode does not open automatically from calendar notifications, but it does solve the jittering video issue.