They need to assume people will use transit and also roads, and increase the capacty of both. The capacity of the bay area road network has been systematically decreased over the last ten years, even as the population has grown.

Also, compared to most other places, traffic laws out here are ridiculously inefficient. For example, light cycles that include a “yield on left turn” step and then skip the left arrow if the lane has cleared are incredibly rare. Also, instead of “left lane fast, right lane slow”, the law is “use whatever lane you’re comfortable in”.

Simply ripping out the “improvements” made in the last decade and bringing traffic laws in line with the rest of the US would increase road capacity by double digit percentages.

(The lack of progress on public transit is also embarrassing, especially given the tax and income levels around here)