From my observation, these new housing developments are built without adequate parking and without improvements to the streets, leading to congested messes and worsening already bad traffic. How people can see this as a positive is unknown to me.
San Jose is mostly zoned single family homes with lots of parking, yet there's plenty of traffic. Maybe it's the ample space devoted to parking and driving that's the real problem, as it forces you to drive.
I think the next step is providing more services closer to people in these upzoned areas, as well as good transit to commercial centers so they can opt out of driving entirely.