pretty much proved to not be true or to such a small number that it matters not. it actually tends to free parking as it simply supplements a commute or drive someone would make with their own vehicle.
this is all down to a union exercising its control over city politicians and having them to their bidding by distorting the facts and attacking those facts instead of the truth
They are also providing employment and income to people. So, I wouldn't worry so much about the congestion impact of it. If congestion is too much, they drivers will drive slower and surge pricing will strike causing demand to drop, thus reducing congestion.
this is all down to a union exercising its control over city politicians and having them to their bidding by distorting the facts and attacking those facts instead of the truth