I see where it's all coming from now.
A 15 minute city is one where your amenities are within 15 minutes walk or cycle ride of where you live. This has nothing to do with restricting cars and everything to do with careful town planning. It's one way to cut down on car use by making them unnecessary.
Another way to cut down on car use is to put traffic restrictions in place, as my city has done and improve mass transit options (as my city has not done).
These are two different but complementary approaches to controlling car use. However, some nefarious person has conflated them to pretend that the 15 minute city is about controlling our use of cars. And then some other nefarious person - perhaps the same one - has twisted things further to pretend 15 minute cities mean we cannot travel for more than 15 minutes.