One way or another, prior development had to provide adequate parking. Conversely, cars cause a lot of problems - pollution, gridlock, greenhouse gas emissions. And I can understand a developer who is committed to changing the world we live in by not allowing parking on their new development. That's awesome!
So, the suggestion is not confrontational. It's going with the dream that the developer is suggesting. We'll never get there if the people who believe in the dream don't commit to it. People have to get around somehow. And if they aren't allowed motor vehicles, then they will push their politicians to invest in public transit.
I think what you're intuitively feeling is that developers don't actually have that vision. Instead, they want to freeload on parking that was provided by others and make life worse for everyone. A few weeks ago, there was an article in HN that suggested Los Angeles could solve their homeless problem by converting every parking spot into housing, which might be true. The idea seemed to be taken seriously with lots of comments supporting it. Yet, that would truly be confrontational and unbelievably disruptive. And kinda dumb since anyone with a map can see that Los Angeles is bordered by hundreds of square miles of open land to the north and west. Plus there's Griffith park, the stadiums, unused warehouses and on and on. So, one has to wonder - was the story truly written by someone who cares about the homeless? Or, was it a developer wanting to increase their profit margin?
If the vision is to get to something like this wonderful "nooks and Crannies" story, then the challenge is getting from the current situation to that vision. I'd love to see that vision come true. Unfortunately, I can't see is a humane way of changing many (most?) existing neighborhoods.
But, what could work would be to change zoning in large undeveloped areas to allow for much higher density housing, walkability, and to link them together via public transit.