Yes, this is correct. Roblox will not bother with rendering anything out of view of the player’s camera, so you can think of it like ‘dynamic nodraw’ that updates based on the player’s camera.
The reason a “nodraw” surface exists in things like Source is because Source pre-calculates the lighting of every brush while it compiles the map, which can get very intensive / slow if you don’t use nodraw because it’ll try to calculate lighting on a surface that won’t even be seen.
Roblox’s take on lighting is 100% dynamic, updating in a 4x4x4 voxel grid, so it doesn’t need to calculate for the entire map in the same manner that things like Source do. I think the need to pre-calculate would be the case if that new lighting system (The one featured in “The future is bright”) was implemented, but that’d probably be handled upon the game being published.
Edit: This is not the case for FiB, it is 100% dynamic.