Comment by jltsiren

Public transit depends on the assumption that some trips are more common than others. If any given person is equally likely to go to any direction, public transit becomes too expensive to build. And it becomes impossible to make the city dense without turning the traffic into a nightmare.

A typical direct bus line starts from somewhere, goes through a number of neighborhoods, reaches a major street, and follows it to a central location. The number of directions that need a bus line is typically much higher than the number of streets reaching the central location. (For example, you need ~10-degree intervals at 10 km from the center to guarantee a reasonable walking distance to the nearest bus stop.) Hence the bus lines eventually converge.

Once you have enough bus traffic that a dedicated lane makes sense, transforming an ordinary lane into a bus lane will make the traffic faster for the average person. It's not a Pareto improvement, as the traffic will become worse for those who drive on that route. But it's not a huge loss for them either. If you already have 20+ buses/hour making frequent stops during the rush hour, the throughput for that lane will already be much lower than for the other lanes.