Bear in mind that positions in international rankings mean almost nothing, as most of them are calculated by looking at the number of cross-linked papers from a university to judge its final score. That immediately puts non-English speaking universities at a huge disadvantage, and I would argue that top-level universities of each country are at pretty much same level despite their ranking positions.
That immediately puts non-English speaking universities at a huge disadvantage
How so? I studied at University of Amsterdam, everyone spoke English at graduate level and everyone published in English. Many faculty where not even Dutch. I would expect the same from any international class university.
I really doubt that. I am sure we can both provide anecdotal evidence, but there is no way 100% of papers are published in English. And you picked a very specific example, because an overwhelming majority of Dutch people speak English at a very good level.
