You have to be aware of Crime, Air and Water Pollution, and Disease now. These addand unhappiness thru the hidden bldgs they unlock at different levels of each.
I don't think the City screen AI is updated (yet) to include these factors in the Avoid Growth, etc selections.
JosEPh
It is as much as it ever was for any other unhealthy effects - basically the AI is reactive, rather than proactive towards unhealthy - it will prioritise health-giving buildings (and de-prioritise unhealth giving ones) more depending on its current health state. Being reactive like this allows it to handle unhealthy it doesn't totally understand (jungles for example in base BtS), and that works fine for property-sourced unhealth also. Of course, it also knows to avoid high levels of pollution, though it sees that as an end in itself - it doesn't explicitly join the dots and connect high levels of pollution to extra unhealth (but it combats both).
Regardless, turning on avoid growth as a HUMAN should directly inhibit the growth irrespective of food surplus, so if it's being ignored for a human player, something is independently going wrong.