I don’t care much for multi-family housing personally. I don’t want to share a wall with anyone, not even a family member and I’m willing to make some concessions for that freedom.
However, recently I became interested in adding an “accessory dwelling unit” on my property to accommodate aging relatives. Despite having the space for a small 500-750 sqft unit on my property, my city’s zoning rules killed the idea. The rules had some interesting limitations like the ADU can’t be more forward than the front of the house, can’t be in a front yard, can’t be more than 40% of viewable property for front, has to be more than 20ft away etc.
Personally I’d be happy with more lax rules around ADU/mother-in-law units/etc. before everything becomes multiplexes.