I don’t know the UK driving rules but it appears that both are at fault. Lamborghini maybe driving too fast and the Mazda made a mistake turning in front of the car without looking what is barreling down the street. Actually watching it for the 3rd time, it is Mazda’s fault. You can see the Aventador almost goes full airborne in the accident. This kind of looks like a Lamborghini parkouring.
Still it’s a sad day. The aftermath.