This is not a bug, and if it was a bug there isn’t much FiveM could do about it.
The more technical side;
GTA uses a technique called LOD or level of detail. It means object that are further away get their model and texture replaced by something that is more easier to render for the game. And that is exactly what you see here. It pops in when you get close and goes away when you get further away.
It might looks a bit strange, but I don’t think GTA is accounted for having players fly-by in no clip.