And a followup to this:https://twitter.com/Martin_Anward/status/1034387593172082689:
"In the 2.2 'Le Guin' update, happiness no longer directly impacts pop productivity, but rather counts towards the Average Happiness of the planet, which affects stability. Under most living standards, the happiness of higher Strata pops counts for more towards this value."
"The more unequal your society is, the less you need to care about the happiness of the lower classes - so long as you employ some Enforcers to deal with the resulting crime."
https://twitter.com/Martin_Anward/status/1034387781781471234