I’m pretty confused by your paragraph describing the “futuristic bioreactor”. It doesn’t seem like we want almost any of those features for cultured meat.
The only parts that seem like they would be needed in are “[...] assembling those molecules into muscle and fat cells, and forming those cells into the complex tissues we love to eat” and “It has precise environmental controls and gas exchange systems that keep the internal temperature, pH, and oxygen levels in the ideal range for cell and tissue growth”
Some (though not all) of the others seem like they might be useful if we were to try and make cultured meat production as decentralizable as current meat production (and far more decentralized than factory farming).
If amount of happiness (or suffering) possible is not linear in the number of elementary particles, what number of elementary particles do you suggest using?