Terrain: Increase base map distance over 2000?

I have a very low-res terrain that is very large (4 kilometers per side). It doesn’t need higher resolution heightmap because it is low rolling hills. So I want the performance boost of having a low resolution terrain, but with high res textures.

Unfortunately, the base map distance seems hard-capped at 2000, which means everything in the distance looks awful. I want to increase the terrain base map distance to ~5000.

NOTE: Terrain.activeTerrain.basemapDistance = 5000; Does NOT work cause unity auto-resets your changes (same with unity grass maxed at 250 meters).

See this: Terrain Question: Increasing Detail Distance over 250 - Unity Answers doesn’t work anymore

Can anyone help solve this issue?

if (Terrain.activeTerrain.basemapDistance != 20000)
{
Terrain.activeTerrain.basemapDistance = 20000;
}

Placed in the update works. Kinda sad.