I don't think it needs to be. Plus, Celebration was still built with cars in the picture. What I want is a city with a perimeter. Within that perimeter you have all the buildings and zero cars. Zero combustion engines. Zero electric vehicles capable of going greater than some reasonable speed limit. Say 30km/h. At the perimeter you have cars for people to drive to other towns and a train station to get them to Toronto / Ottawa. Maybe a small airport.

Once you change from thinking "oh we just must have cars here" to thinking "how would we solve problem x without cars" the whole city can be made to be more vibrant. We can't let our children out of our sights in modern cities they're so dangerous. That's madness!

In terms of authenticity, here I partially agree with you. I do not intend to emulate an ancient European city. That's dumb. But I don't want the city to end up looking like shit like most of Canadian cities do with their completely mismatched building styles, billboard ads, tacky chains, and telephone poles all over the place. Instead, at the city formation you get good estimates of what types of natural building materials are near by (the types of wood, clays, stone, etc) and you hire teams of architects and city planners to design a set of cohesive style guides. There should be room for custom flourish, but the city should still look like a cohesive whole. There is no reason to use concrete for anything other than subterranean piles. Use large flat rocks for streets. Yes rock streets are more expensive but they look much, much better and because we have density from day one they might be 10x the price but we should only need 1/10th of the pavement by area.

Also, by creating a hard perimeter around the city, there could be a real set of community gardens just outside of the city for things like herbs and other expensive plants. We wouldn't have to choose between city life and connection with nature.