Are you suggesting birth of a nation and metropolis are of similar quality? I found metropolis pretty riveting, some of the imagery was superb as well as the city scape sets. It's a while since I saw it but as I recollect most of the film is about the division between the workers and the owners of the capital. I can't recall drawing any conclusions on what stance the film was taking; I should watch it again. I keep meaning to buy the blu ray version as I believe that incorporates a further print recently discovered and matched to a contemporaneous score is now believed to be very, very close to the original version. I find a lot of it disturbing, but I find German expressionist films much more interesting than US films of the time. I am enthralled by nosferatu, der golem and the cabinet of dr caligari.