He shouldn't have pulled in without indicating, it's natural to tail gate a bit if they haven't signalled ahead of time. And his getting out of the car is an overreaction. But the poster should also pay attention to his lane discipline on roundabouts. Everyone makes mistakes.
The HGV driver (dashcam driver) was NOT tailgating the Volvo. The arsehole in the Volvo pulled out in front of him without indicating and drove too slowly. Obviously trying to take the piss.
He's weird stay away I won't let my grand daughters near him