“The trip must be between 200 and 300 miles. Their research indicates this is the sweet spot between being more than a convenient car ride, but less then a convenient plane ride. I'll note that LA -> LV is ~180 miles, whereas LA -> SF is ~340 miles.”
That’s a function of the train speed. If the train traveled at 300 mph, then LA<->SF becomes faster than Brightline’s 180 mile LA to Vegas route, which looks like it will average 100 mph.