Boethius (480-525AD) had read a lot of Greek stuff during his lifetime. He wrote a description of music theory that was (and still is) being used. https://classicalliberalarts.com/wp-content/uploads/BOETHIUS-Bower-1989-Fundamentals_of_Music.pdf His writing was very influential.
Boethius seems to be the first person (in Western Music Theory) to call slow vibrations "low" and fast vibrations "high." Later Western theorists followed his lead. Boethius had no way (I think) of measuring the frequency though.
I suppose other choices could be made; I think Norwegian uses bright vs dark and other languages probably make other choices. In early Western theory, B was called a "Hard B" and Bb a "Soft B" (leading to the German B vs H usage.) Some languages use soft and and hard to refer to minor and major chords.