You're limiting your framerate with RTSS. The first thing I noticed when trying this out was that RTSS does not report frametimes properly with this game when you're capping the framerate. I did the same thing, and my line is perfectly straight like yours, but there's still hitching and stuttering.... it's not smooth at all. This same thing happens even when I limit it to 40fps (which I NEVER drop under) or hell even 30fps. At 30fps limit, there's STILL noticeable stutter in the way the game paces frames.I'm not necessarily saying I'm getting a flawless "no stutter at all" experience. Sorry for poor choice of words. I'd say %98 of the time it is smooth. There are hitches here and there when a new map is loaded or a new car shows up in the scene but it is definitely not constant enough to deem it problematic or immersion breaking. They definitely do not happen with higher end systems with more memory. But from your example, it even happens with medium textures, but they do happen even more rarealy on my end with high textures. So could be that my preventive measures in disabling steam's hardware accerelation and restarting dwm.exe may have a part in play to get a bit more smoother experience.
In my case, a framecap also eliminates problems in a major way. 50 FPS cap especially. Giving GPU some headroom seem to have a positive effect.
It's definitely problematic...
...because this game is EXTREMELY INCONSISTENT in every single way. You can be in a room just spinning the camera around and there will be uneven framepacing at completely random intervals... and then you can also be running through a much bigger environment, looting and shooting, and frametimes can be smooth... then again change for no apparent reasons.
There are serious issues going on under the hood here which completely ruin the framepacing in this game.. and these things MAY be less noticeable/frequent at the extremely high end... but they are 100% there.