Somehow I got the orange negative SR because of this. He got nothing! What the hell!?
If we could take the understandable emotion out of the situation for a moment.
You get -SR for hitting another driver from behind and from the games perspective you approached from the rear at a higher speed and made contact with another car on the normal line. That's just how the game works and it's not perfect in its judgement.
Also, he was closing the gap to the kerb and was always looking like he was going to strongly defend that line, so taking a line straight for a narrowing gap onto a grass verge is not the best line for you in that situation. You were heading for conflict from the moment you committed to that choice.
I'm not sure what view you drive with, but you did a slight left correction of your line before you got to the kerb effectively making the gap between you even smaller.
If he would have been perfectly steady and then steered into you once you were along side, it would be clear there was nothing you could do. But as it was, he made clear (rightly or wrongly) that he would block your attempt to pass.
Using the visual clues of another drivers style can help devise a strategy as to where you can pass cleanly. Not always possible on very short races but that's only negated by more time in the qualifying stage to be in front of slower drivers from the outset.
Seeing how he was driving and having the speed advantage you had it may have been better to line up directly behind him to gain even more from the drafting and then at the very last second take the pass on the left keeping a very slight leftward left angle to increase the chances any blocking move would have reduced effect and you would have been heading into open track rather than grass verge and a barrier.
Everything is easier in hindsight, but it's more important to learn how to deal with these situations as they are regular and very difficult for a game logic to regulate. Easier for you to learn and adapt than to expect everyone to move out of the way when you approach. That certainly doesn't happen with racing in the physical world where lives and machines are at risk, so it definitely won't happen in a virtual world
Don't get me wrong, I understand your point of view here, as I and many other experience the same tactics all the time. The point is, you were faster, which is the hard bit, now you need to find a way of using that speed to get past, let's call them defensive, drivers.