The big mirrors are completely obscuring his side view. Truck design is all wrong. They need to get with the times.
The A-pillar and mirror cluster is going to limit his view when taking the left turn and "could" have obscured the motorcyclist. He’s also likely to be checking his nearside mirror immediately before taking the turn so could have missed him on the approach. He takes the turn relatively quickly and is unable to swing out further to the right prior to taking the turn as a skip truck is coming in the opposite direction and he does not wait for it to pass. You often see HGV drivers ride over the pavement on tight corners like this, but there is a woman with a pram at the junction…
I doubt the motorcyclist would have seen the indicators until after he shoulder checks at approx. 6 secs and by the then the HGV is heading straight for him. In real time, it happens very quickly.
HGV cab re-design cannot come soon enough as these vehicles are compromised in urban areas and their drivers are subject to mistakes and cognitive overload.