At a first look the dynamic looked cristal clear: after another slow get-away, the #33 dived into La Source as he used to do in previous year. The contact with Raikkonen was then inevitable and both the drivers paid a high price for that.
Then onboard footages were released by Formula 1's official social media accounts and the story gained another prospective.
From Max Verstappen's view the divebomb is still clear, but something else to be added is found in Kimi's and Perez' ones.
Approaching turn one's braking zone, Kimi is on the left side of the track. The Finn then decides to cut off Sergio Perez, who was going for the move on his right side. In doing so, Raikkonen takes a long diagonal line that brings him right to the apex on the opposite side of the track. Meanwhile Sergio Perez, not expecting the move, is forced to lift the throttle. Despite that, the front wing of the Mexican makes contact with the right rear tyre of Raikkonen, not causing a puncture just for a matter of luck.
From Kimi's onboard footage it's clear that the Finn is constantly looking in this right rear-view mirror, checking Checo's position. What he didn't know until he was almost into the corner is that, unsighted because of the Racing Point, Max Verstappen was aiming as well for the apex of the right-hander. At that point we don't know if Kimi managed to see the Red Bull or not, nevertheless in such a small fraction of a second it would have been difficult to properly react. At that point, yes, the crash couldn't be avoided: both of the drivers were too committed for both of them to make it through La Source unscaved.
So, end of the day, who was the guilty man?
Having analyzed the dynamic, it's easy to agree with the stewards' decision, that labelled the crash as a 'racing incident': turn one at Spa is always chaotic and, with such a small margin, conctats are often unevitable.
Nevertheless, both the drivers are in some way responsable for the collision: Kimi crossed the entire track on the run-down to La Source, a move that is surely going to bring some risks. The contact with Perez alone (who was still behind, so was meant to brake) means that the move was a bit too aggressive. Furthermore, Max' front wing was beside Kimi's cockpit when the Finn went for the turn. According to the rulebook that would be enough for Raikkonen to be supposed to leave room, but at that point his eyes were obviously pointing at the apex.
Max wasn't innocent as well: probably willing to perform in front of the Orange Wave, he went for a really late dive, similar to the one that took him out of contention back in 2016.
He actually didn't violate any rule in doing so, but the move itself was silly, being just at the start of a 44 laps race.
Kimi lost a chance of being 'best of the rest', looking at the great pace of team-mate Antonio Giovinazzi, while Verstappen likely throw a P4 finish chance away: Vettel was suffering so much with tyre-wear that Red Bull would have had a chance of jumping him.
If I had to give a percentage of fault, it would be 35-35-30%: 35% to Raikkonen, his move was as opportunistic as risky and didn't pay off. He had to expect someone on the inside, even if the Racing Point prevented him from seeing the Red Bull. 35% to Verstappen: a silly divebomb that was very likely to end up in a crash. It was also useless, since he would have overtaken both Perez and Raikkonen straight away in the opening couple of laps.
Last but not least, 30% to the race situation, with the Racing Point preventing Kimi from noticing Max.