I think this is at least in part due to QS ratings. The first EU university enters in the 40s or 50s of the list and Australian universities seem perhaps overr

I think this is at least in part due to QS ratings. The first EU university enters in the 40s or 50s of the list and Australian universities seem perhaps overrepresented. Closer to the ground, or, let's say, being more grounded in mundaneness, I think it's also because a lot of excellent papers are never translated to English. Asia "gets" this and pushes their English papers. FWIW, Galois's memoirs have still not been translated, as far as I know. Oh yes, and ETH Zurich is at least in the top 10 of the QS list.