I lived in a city with argubly the best public transportation in the world. there were still plenty of times a taxi was needed. going somewhere when public transportation stops
is one. Another is when carrying something large. when going to something formal in bad weather, when too sick to walk, ...
I don't see it reasonable to ban private cars and then allow rich people to use taxis. Everyone should be treated equally in this case. Meaning no private transport for anyone. And basically there is always the option not to go when the weather is bad or there is no public transport. Which I think would be entirely valid choice to force on everyone. Also there is ways to move large objects without any powered tools.
The rich are always going to have advantages over the poor. The point of banning cars isn't to punish the rich or to make everyone equal. The point of banning cars is to reduce the traffic and pollution on the street and make the city more livable and healthy.
There are less abled people for whom you'd need some form of frequent or on-demand transport close to their position. Taxis fill that role in the current system.
Wouldn't those be inefficient? Isn't it better to force absolutely everyone to bigger units thus taking care of unit economies in emissions. Like full-sized busses going every 20 minutes to hour just so they will fill up.
Perhaps, but why would banning taxis(and cars in general) necessarily be one of those requirements? Seems to me a better and more pragmatic way is to dedicate more resources to electrifying the transports and banning the use of fossil fuels as soon as possible.
I believe that for a modern society to function a point to point family sized vehicle is required somewhere there in the mix.
So why not fully embrace them then in cities? Allow everyone to have their own private family sized vehicle? With designated free parking spot too to allow the convenience. Ensure that there is plenty of road capacity and that the travel is not impeded by those with lesser energy requirements for starting and stopping like pedestrians and people using bicycles.