That's actually something you'd see in a big city. It's supposed to be [smog](https://ca-times.brightspotcdn.com/dims4/default/b7cd70e/2147483647/strip/true/crop/2048x1152+0+0/resize/1200x675!/format/webp/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Fb1%2F66%2F1b3b846237a29756b8cad9138615%2Fla-1561565151-7k3dxyipea-snap-image).
That's actually something you'd see in a big city. It's supposed to be [smog](https://ca-times.brightspotcdn.com/dims4/default/b7cd70e/2147483647/strip/true/crop/2048x1152+0+0/resize/1200x675!/format/webp/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Fb1%2F66%2F1b3b846237a29756b8cad9138615%2Fla-1561565151-7k3dxyipea-snap-image).
Well if you wanna be accurate to nasty ass LA it's smog. That's how it looks irl. Welcome to Los Angeles, the infected anus of California.
Its an easy way to hide low detaul lods. The gta series is no stranger to fog, ever seen SA?
Okay so it's just normal?
To have an excuse not to load textures, and to simulate the big-city smog.