On the Intuvia it's just a allen bolt which goes through the mount and into a slot on the head unit itself. With a bit of know how and time it would only take 60 seconds to remove, so no good if bikes are left outside for extended periods.
Other than changing to a non removable head unit the best way is to ingrain in everyone to take it off when they walk away from the bike. The added bonus being that if someone tried to hop on and ride it away they won’t have any power without it.
On the Intuvia it's just a allen bolt which goes through the mount and into a slot on the head unit itself. With a bit of know how and time it would only take 60 seconds to remove, so no good if bikes are left outside for extended periods.