If a person theoretically spoke French and English but had not yet studied German, would that make such a leap more difficult?

From my experience, people get along pretty well in Germany even if they know only English. Especially in large cities like Berlin, where they are likely to get such a job. So many people speak good English here, that it is actually hard to learn German, because the natives don't want to speak German with you :-). I'm in research, and half of my institute here in Berlin are foreigners.

Of course, it still helps a lot to learn German - and I think you miss out on a lot if you don't learn the language of a country. Also, you'll need a friend or colleague to help you with administrative stuff in the beginning (which may be in German only).

Going through the whoishiring.io job offers, Germany has a comparatively high number of job ads written in German (even for remote positions).

This is very interesting, as it may point to a less international work culture (although this is in the process of changing), which this translates to a "possibly yes" answer to your question. Of course, whoishiring.io may not reflect accurately real world, still, I don't think it's random.

Answer of the type "N people work here in Germany without speaking german" are not correct answers, since they don't imply a comparison (the question is comparative).

I know about 6 American software engineers who don't speak a lick of German working in Berlin.