I’m confused doesn’t the 101 corridor go down the coast between Salinas and San Luis Obispo? And doesn’t the existing Coastal Starlight go along it?

I’ve actually taken that train. It takes 12 hours. A lot of that is padding because of the unreliability of the tracks, but also because the route is really tight. I doubt you would be able to improve the tracks there such that 5-6 hours would be possible, let alone the 2 hours through the valley.