People are calling for radical change to their cities as they realize the poor economics of urban sprawl and suburban development. You do have a good point though as transit, density, and mixed zoning all work best when used together.
The shift to transit and walkability will actually make exisiting roadways and highways less congested and better serve any delivery vehicles using them. We won’t rip out all existing roads, but we will stop building a new lane every 5 years.