With a real carbon tax these numbers would actually be further apart. I was surprised to learn that in the real world trains are not more efficient than a the average car when measured in passenger mile per gallon equivalent. And trains are much less efficient when compared to a high MPG cars like a Prius. In fact I'd be willing to bet that there are only a few of city/regional public transportations systems in the world that are more energy efficient than just taking your Prius.

https://theicct.org/blogs/staff/planes-trains-and-automobile...