If having slaves water your garden makes it grow does that work?
If the slaves feel fulfilled and by all means happy, sure.
So it only works if it is voluntary?
If the majority of sentient organisms must experience the illusion/or actually the freedom of association and freedom as individuals in order to be happy, so be it.
So you'll let me be free if you think I need to be free to be happy or if I think I need to be free?