The real area of focus for reducing traffic and vehicle usage should be the San Fernando Valley corridors (Sepulveda/405, the 5, and the 101 to San Gabriel Valley). Iirc from a recent report on KPCC there's like 600k daily commuters between the valley and the southland, and another 700k between the valley and San Gabriel Valley.
We have one metro stop in the SFV, which serves the 3 million residents. It's no wonder it's surrounded by a massive parking lot, and most commuters don't use it anyway.