This 432 Hz theory is sort of like saying that if we measured the meter as being slightly shorter, people would have an easier time running a 5k.
Music exists in multiple keys, and a song can be in a high or low range regardless of what key it’s in. Changing the standard tuning wouldn’t fundamentally affect anything.
Also, did the study authors simply taking a recording and pitch shift it down to 432 Hz? That would affect the tempo of the song as well as the pitch. Even if they performed time stretching to keep the tempo the same, it shouldn’t be surprising that lower pitches make people slightly calmer than slightly higher pitches.
Music exists in multiple keys, and a song can be in a high or low range regardless of what key it’s in. Changing the standard tuning wouldn’t fundamentally affect anything.
Also, did the study authors simply taking a recording and pitch shift it down to 432 Hz? That would affect the tempo of the song as well as the pitch. Even if they performed time stretching to keep the tempo the same, it shouldn’t be surprising that lower pitches make people slightly calmer than slightly higher pitches.