If you read James Allen's Belgian GP verdict on what happened it makes some since, but when Kimi quite fairly forced Lewis off at the chicane they were side by side. So after when Lewis gave the position back passed behind Kimi, in my opinion he gave him ample advantage.
It is not McLaren’s fault that Ferrari is not as good as they are in the wet and to penalise Lewis and McLaren because they have an advantage in the wet is wrong.
What was Lewis meant to do?
How far in front was he supposed to let Kimi get before commencing racing?
If the ball was on the other foot would the outcome be the same or maybe just a fine.
john d