Do you think these organs were designed just to look cool? No, their design is highly specific based on countless acoustical variables.

How about the cathedrals themselves? Were they really designed just to look cool too?

Cathedrals were designed to resonate. It is obvious the vibrations had serious importance. The things we call "divine" today like spiritual healing, levitation, sinking buildings, have all been demonstrated to be possible with help of sound. So maybe it is the sound that they worshipped.
From Telegram chat
https://t.me/antiquitecharchive/3851?single

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