FYI/BTW for the people who are saying that interiors and terrains lag less and more bricks will lag more:
This is exactly the reason why they're not JUST adding shadows and shaders, they're also improving how the game itself will run. Most likely, in the coming v21 update, it will only lag if you have a really really really really stuff/old computer.
Heed is probably going to disagree with everything I just said.