And the issue here is pollution, not traffic. These shared cars are electric, so not a problem.
In the spring lots of particles are released from the road, those particles have slowly accumulated during a long period of wet weather. Decreasing traffic reduces the amount of those particles that are launched up into the air, not by much, but hopefully enough to not be fined for it. I guess electric cars help a bit but not enough by a long shot.
There are three ways to solve mobility in cities
2. public transport
Trying to use cars for personal transport has failed for all cities that has tried it.