Why do you think different language Wikipedia's have different sizes, outside of the popularity of a given language?
Piotr, if you model organic editing production with a Poisson distribution, which is reasonable for a first approximation, 3x+ disparities are just natural for the same population sizes:
https://en.wikipedia.org/wiki/Poisson_distribution
I'm not sure the images in that article capture the wide platykurtosis of large Poisson distributions.
Best regards, Jim