I'm confused what these two settings sliders (Steering Non-Linearity and Steering Sensitivity) actually change, and how they are different from one another:
Steam Community post has a broken link to a graph. Here's source for screen-shot.
Reddit doesn't explain it simply enough:
I don't mean to sound like an ass, but it sets the steering linearity. If you have a steering wheel, it means when you turn it, to what extent and how even the wheels respond in game. For example, if its set to completely linear the steering in game will turn exactly as much as you turn your gamepad / steering wheel. That means, if you turn your steering wheel irl 5 degrees, in game will turn 5 degrees. However, if its not linear it will turn less, it might only turn 3 degrees in game and then at the end of the rotation “catch up” or ”compensate” and turn very much in game for very little actual rotation on your irl wheel. I find the option helps a lot if set to non linear, especially if you have an old wheel that doesn't do 900 degrees rotation, otherwise while driving fast its very easy to accidentally turn too much.
How does this differ from Steering Sensitivity?