What is MobileAccessoryUpdater and why it runs on my MacBook?
It seems that fud is the firmware update daemon of com.apple.MobileAccessoryUpdater that presumably is responsible for firmware downloads for bluetooth peripherals and running the firmware update daemon
(hint for fud found here)

To unload/disable it run in a terminal (this will persist through restarts, but probably not OS updates):



sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.MobileAccessoryUpdater.plist


To enable/load it again run in a terminal:

sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.MobileAccessoryUpdater.plist