The author is comparing electric cars to gasoline powered cars. The idea is that the cost of paying to use someone else’s electric car—even with a markup added—

The author is comparing electric cars to gasoline powered cars. The idea is that the cost of paying to use someone else’s electric car—even with a markup added—would be less than your current gas car’s cost per mile. The per-mile cost also includes the capital outlay for the car itself. In other words, it might not make sense for you to pay $40,000 for a new electric car, but it could make sense for three people to split that, and drive each persons per-mile cost down. All of this is in reference to how fast the switch over could happen, and is why it might be much faster than any of us anticipate.