With version 2.44.52 of the firmware the watch does not vibrate after a successful compass calibration, it plays a sound instead.
Also, at least from my experience, unintended calibrations are (almost) non-existent.
Here is link to that version, in case it might be useful for your experimentations or if someone wants to downgrade to it.
I never updated past this version as it was very stable for my needs and I remember later ones introduced the backlight-related problems, the vibrations, battery drain for some, etc.
To be fair, I fave not actively used my 9PP since the end of November 2025.