I hate the countries that do this because it doesn't even make sense as a signal. We already have a horn. They are wasting a channel!
At highway speeds, engine, road and wind noise usually make horns inaudible.
In Serbia, on top of get-out-of-my-way, it's also used to signal go-ahead, but also "police with speed radars ahead" to incoming traffic.
It also doesn't make sense because "get out of my way or I will ram you" is the default state of operating a motor vehicle. Not the goal but the physical reality of it.