It’s also less than that in travel time, since CAHSR goes at its full 350 km/h on the Central Valley vs just 130 km/h on the Caltrain corridor from SF to Gilroy. It adds about 10 minutes to non-stop travel time.
The real benefit is opening the Central Valley to commuter development. San Jose to Madeira on CAHSR is around 45 minutes, not much more than commuting from Palo Alto with current traffic on 101, and so it’d open vast tracts of land in the Central Valley to housing. It might actually be practical to work in the Bay Area on something non-tech, live in a SFH, and commute less than an hour again.
They are running multiple trains. SF to LA non-stop trains won't even stop at stations like Gilroy or Madeira. The all-stop trains will preference commute hours. The seats are non-rivalrous: Central Valley commuters aren't even going to be on the same train as a SF to LA business traveler. It seems reasonable that fares would differ, and that traveling just 1-2 stops from SJ to the Central Valley will be a lot cheaper than going from SF to LA.
This really depends on how it ends up being priced.
In Germany, you can pay for a year-long high-speed rail all-you-can-ride pass. It costs just under 5000 Euros, which is very reasonable if you're using it every workday.
This is a bit like AWS pricing. If you book an entire year of usage up-front, you get a much lower price. Casual users pay much more per use.
The real benefit is opening the Central Valley to commuter development. San Jose to Madeira on CAHSR is around 45 minutes, not much more than commuting from Palo Alto with current traffic on 101, and so it’d open vast tracts of land in the Central Valley to housing. It might actually be practical to work in the Bay Area on something non-tech, live in a SFH, and commute less than an hour again.