[content warning: not answering the given question whatsoever]
I put forth that they are not futuristic. They are present-day, present-time, not pretending to be beyond the present reality, but merely cutting-edge.
To someone who has grown up in a relatively very undeveloped area (consider rural Sudan) or even somewhat undeveloped areas in the West (rural North America), I imagine many Western cities would seem 'futuristic' relative to their life experience. Towering skyscrapers, underground rail networks, animated LED billboards and cameras everywhere, and if you're lucky, slick 'modern' designs for buildings and infrastructure. But, to a person raised in these cities it probably wouldn't be futuristic. Many of these things are kind of common in cities, actually. They'd look at the other communities as 'underdeveloped'. It's all relative!
So, in the same way, I think that China's modern cities aren't futuristic but merely present. The US infrastructure is notoriously underdeveloped given their power and technological capability. I don't see why (political structure aside) they couldn't build such a planned city. In fact, they generally lag so far behind other Western countries when it comes to civil infrastructure, political structure and social services that I think calling the US a developed country is an outdated mistake. China, on the other hand, has rapid development.
China isn't in the future. We're stuck in the past.