Rider and Pillion Weird Spill in Russia [Video]
One of the potential causes was that the rider got scared by the approaching car, braked hard during the turn and crashed. However the car was not traveling too fast and the distance between it and the bike seems pretty generous for a safe turn, and even some swerving, if needed.
On the other hand, we can't tell for sure who was to give way in this situation, but it looks like the bikes had the right to pass. It's somewhat of a relief that nobody got seriously hurt after such a spill, and no Russian-style axes or guns blazing were to be seen. Just watch your ride, for nobody else will.