Basically, the concept seems to be concentrated on separating a person from their car. Sorry, but restricting a person's ability to travel by means of further "taxation" is a form of control. Vehicle ownership already has numerous costs designed to support the highway system. Conspiracy or not, where does this new tax money go?
Has anybody given any consideration how easily another pandemic would spread in one of these cities? There seems to be a utopian vision that everybody will be happy and mingling in the empty streets. Sorry for the questioning attitude- still waiting for the source of the first pandemic to be divulged.
Overall, the concept sounds efficient. Most likely a good idea. I still don't think there is much variation from what already exists in larger cities. In NY, it seemed that a person needed to be "well off" to afford the expense of vehicle ownership. It appears that the 15 minute city concept envisions that process as well. As always, the source of issues occurs when some try to force their ideas onto others.