I'm not going to apportion blame to Max, but I will try to highlight a couple of his reactions from the start, as well as those of Raikkonen. I've made a rough attempt to stitch a few stills together to elaborate my perspective.
Immediately from the start Verstappen moves toward Vettel, Vettel likewise moves slightly toward his left (our right). The net gap between Verstappen and Vettel has closed by a full car width before Hamilton crosses the start line. Raikkonen has got the start of his life, sees the space Verstappen has created, and moves left to continue his momentum, getting a big tank slapper as he begins to pull alongside Verstappen.
By the 4th frame Raikkonen is halfway alongside Verstappen, Vettel has maintained his leftward trajectory, and Verstappen has continued straight. Verstappen is looking straight ahead, not suspecting Raikkonen is there, and not adjusting his trajectory away from Vettel.
The fifth frame is where Verstappen alters his trajectory in response to Vettel, who continues to veer left. Verstappen very clearly steers to his left. He isn't looking left though, and has not noticed Raikkonen. Raikkonen is almost alongside Verstappen at this point.
In the region of the sixth, seventh and eights frames, Verstappen notices Raikkonen and makes a big correction, but Raikkonen and Verstappen are now very close together, and Vettel continues to move further left. At this point, Raikkonen does move very slightly right, and Verstappen moves slightly left - cue DNFs for all.
I've tried to get Raikkonen and Verstappen's movements in-line so that we understand who was doing what when. There is a thin line indicating a perfect horizontal, but the camera angle isn't dead straight on Raikkonen's footage, so his wheel doesn't align 100%.
It's pretty clear that Verstappen initially moves left, then straightens his wheel. This would have him moving slightly left with constant path. As soon as he notices Raikkonen, he corrects to the right very sharply, but then he straightens his wheel again, probably in response to Vettel's continued path leftward. The final position is left-leaning, by which stage they're going to have an accident.
Raikkonen's movements are far more subtle, but I can corroborate that Raikkonen makes a very small adjustment to the right, pretty much as his front wheels pass Verstappen's. At this point, Raikkonen is edging slightly to the right, and Verstappen slightly to the left - cue DNF's for all.
Very difficult to apportion any blame here. A confluence of factors caused this in my opinion. Vettel moving consistently left, without any regard for any driver other than Verstappen, being a significant factor; Raikkonen's start, putting him in a position neither Vettel nor Verstappen had bargained for; and the rain - Raikkonen and Verstappen were both correcting for wheel spin throughout this sequence, so it goes without saying that neither were fully in control of the situation.
Overall, Vettel can blame himself for forgetting a race can only be lost in the first corner, but I find it difficult to suggest his actions warrant a penalty more harsh than he inflicted on himself.
