>>1696881>move people across Los Angeles county at high speed You have to slow down, stop, take on/drop off passengers, which adds a lot of time.
Part of a high-speed system is stopping infrequently. LA is big, but polycentric in a way that would make it uneconomic to try high-speed expresses connecting major centers, as ridership at any given one would be rather low, especially in the absence of a dense network of connecting local mass transit.