The only use this really has is in replacing the plane traffic from los angeles to san francisco. that would make sense if we were facing major airport congestion on either end, but I don’t think that BUR, LAX or SFO are in bad shape. OAK’s line for southwest can get ugly, which is why i use business select.
it would be more interesting to see if it takes seasonal commuters off of the 5 - i.e. students, but there can’t be enough of them going between the bay area and LA to make an appreciable difference.
Those flights are under 1 hour, and the distance is 347 miles as crow (or an airplane) flies. But obviously the train can't do that, so it will have to go around the mountains, and it can't (unlike the airplane) keep the top speed most of the way. The 220 mph top speed will be probably like 150 mph average, and the trip will take 2 to 2.5 hours.
People who rarely go from SF to LA probably will pick the airplane. People who regularly go there will have a choice to spend 1-1.5 hours extra on the road (one way) or to pay extra (maybe) for the airfare. Considering that most travelers are businessmen, they will likely stick to airplanes, especially because the infrastructure is already in place, and because if you are switching flights at LAX or SFO then taking another airplane is a logical choice, as opposed to leaving airport and taking taxi to the rail station (that taxi alone will eat all the savings.)
I don't go to LAX frequently, but when I did Southwest ran a bus-like service there, and very cheap too. I used Oakland's airport only once or twice and don't remember how it looks like or what lines it might have.
it would be more interesting to see if it takes seasonal commuters off of the 5 - i.e. students
I often go south on 101 and north on I-5. I also traveled on I-5 from San Jose to San Diego. I don't have an impression that I-5 is particularly busy to begin with (outside of LA,) but when it is busy it's because of those huge commercial tractor trailers, not because of students. Besides, students in the Bay area are probably at Stanford, and those can hail from anywhere, LA being probably not a likely origin.