Some languages have more words than others, especially 2-3 letter words, which would probably allow for a higher average game score.
For example, although the same language, English, the Collins 2019 UK dictionary, compared to the NASPA 2018 US dictionary has much more words in general, especially game-changer 2 and 3-letter words like "ze", "zo", "ja", "qin", and "zea". https://scrabbleplayers.org/w/How_Collins_differs
In fact, top players/computers will score an average of 450 playing CSW (Collins UK) versus playing 425 NSW/TWL (NASPA US).
I'd like to know what language allows for most scoring potential. I would assume the language with the largest dictionary, heavily biased toward 2-3 letter words for hooks and parallel plays, would score the most. I'm not sure what language that would be.