Kicked up dust / sand can be seen in RL racing videos, most often where cars drop a tire onto worn edges of the grass, ends of rumble strips, abrupt transitions with extended pavement, etc. It's quite common, especially where the soil content has more sand and during dry periods but, after low-lying areas (potholes) along the track have dried up.
I'm not saying it's 100% what the developers are going for but, it seems pretty logical and would be a unique touch and great detail imo.
I'm not saying it's 100% what the developers are going for but, it seems pretty logical and would be a unique touch and great detail imo.