Well it's not only a question of shadows, I also mentioned about them being flat and just floating there. Yeah, you can make them look fine from face-on, but how about a view like in this pic? They're flat. They have no depth. That's just the way that sort of thing is, as I said, the nature of the beast.

Yes, of course, Trekkie Girl, I'm aware that eyebrows cast shadows. I really didn't think that the physics of light stops at a certain size.
But one thing real eyebrows don't do is cast shadows as if they were hovering over the head like a patch of sod dropped from a building in the second before it hits the ground.