Theory on Gestrals and Jazz:
"They will never understand, one day, this place will be full of casinos and everyone will listen to jazz."
There's more than one gestral with dialogue raving about jazz. Monoco's theme, Golgra's theme, and other gestral-adjacent songs in the soundtrack are very jazz influenced. Why are the gestrals so into jazz?
My theory is that real Verso, being a musically-inclined kid growing up in the late 19th century, probably loved jazz. It was the up-and-coming music of that era. Of course he made all his cool gestrals love jazz.
I imagine jazz at the time had the impact that hip-hop has today - it's a new and unique sound that makes grumpy old people wrinkle their nose and say "back in my day, they used to make real music". Imagine Verso coming home with a newly purchased jazz record, carefully tucked between 2 classical records so as not to cause a scene, being intercepted by Renoir arriving home, who just sighs and says "Don't play this while your mother is home, you know what she thinks of this garbage."