I'm guessing that we don't want people to write papers in a language where they don't understand "as of my last knowledge update", as probably a lot of terms in their paper have more advanced language than that.
Would be better in those cases for people to write their paper in their native language and let readers translate it for themselves.
It’s not a black and white problem. Some people may have good ability to read but not write/speak a language (I’m that way with Spanish) so the cases will vary as to which would work best user or author translated, it could be good to include both version in any given paper and fix both problems.
Would be better in those cases for people to write their paper in their native language and let readers translate it for themselves.