The left used to love car-pooling. Forcing multiple people into the same car was good for the environment.
Then Uber built a business model around paid car pooling. It reduced the number of people on the road. It was an easy solution to drunk driving. And it allowed people to make money on the side.
So of course the left hates it.
New York's campaign against Uber is typical of the intersection between cronyism and leftist politics that defines Mayor Bill de Blasio's misrule of the city. What does repressing Uber and Lyft drivers for the benefit of the taxi industry accomplish? Aside from the obvious crony goals, it taps into the left's resentment against companies that make their own lifestyle possible.
Why did the left switch from liking the idea of forcing multiple people into one car (Uber Pool and Lyft Line do that quite well) to hating it? Beneath the rationalizations is the simple fact that what the left really wants is for people to be miserable.
When pooling became useful and innovative, when it made people's lives better instead of worse, the left turned against it.
What the left really wants is to make people miserable. Its symbolic gestures, e.g. recycling your trash right before it goes into a landfill, serve no useful purpose except to punish people. And when a leftist policy stops being punitive, the left will go after it.