Two reasons why the current Uber/Lyft situation causes more traffic than the old taxi situation: 1) The bar for driving a car in the city for pay has been lowe

Two reasons why the current Uber/Lyft situation causes more traffic than the old taxi situation: 1) The bar for driving a car in the city for pay has been lowered significantly from the old taxi medallion system. This makes for a much larger fleet of cars in the road. A great thing if you have memories of walking down the street at 1AM, looking over your shoulder for the taxi that never came, but a bad thing for 5 PM traffic downtown. 2) The city has a decent amount of taxi-specific traffic infrastructure, such as taxi parking / cab stands, which may not be used by Uber or Lyft drivers. Instead of parking in designated spots, we see them doing things like stopping in bike lanes or circling the block.