Even without the fact that it's so old, it's still a well made animation, and would deserve a 6/10 regardless.
I'd suggest watching it if you're reading this and you haven't already. It's around 4 minutes and is rather interesting. The only drawback I can think of is that there's no audio, but obviously that isn't really a fair complaint for the film, considering it's age.
In conclusion, the art style & the historical significance of this film is reason enough for a 9/10.
