I don't know if this is a bug and I don't know if mojang knows this. But the max render distance on realms is set to 10 chunks and the max minecraft render distance is uped to 32 chunks. I find it very annoying and I think it takes alot away from the gameplay. You can see it on the screenshots.
MC-72256
Minecraft Realms server render distance is capped at 10 chunks
Resolved
Works As Intended
0
To prevent disturbing the other servers hosted on the same hardware, the render-distance is limited, chunkloading are quite a load on the hardware.
If you wish to have a larger renderdistance, I'd suggest running your own server.