I don't see what the difference is between being good at something and it being easy. I think the prices of these things are indicative. The fact that an ICE has a bazillion parts is superficial, aesthetic, and irrelevant. A bicycle chain has 400 moving parts, state-of-the-art metallurgy, and costs $10.
I guess it's a question of whether battery production will one day be easy as well. Certainly, 200 years ago modern ICE production wouldn't have been easy, so maybe we're just at a similar point in the history of battery production.
