As a useful initial segment, the Valley line makes little sense. I agree. The traffic potential doesn't exist to justify it as a stand-alone project.

However, it's all they could build with $10-15B available from the original bonds, fed funds, and a few other dollar dribbles. If they ever expect to complete a SF-LA line like Prop 1A required, something in the middle is necessary, of course. And, think of it as a Concord Test Track writ large. So it's not a total loss, unless the rest of the system is abandoned permanently.

The original justification (replace air travel between LA and SF) was laughable, though of course some of the rubes (enough of them to push the Yes vote high enough) were taken in. That, along with enough others who saw it as a source of money for useful transit improvements that would otherwise be difficult to pass. Nobody other than the actively clueless could have thought that the line could be built for the $35B amount claimed, even at the time, let along the $10B bonded. But it was never intended to be more than table stakes.

As for airport service: HSR using the Caltrain line would have reasonably convenient SFO access via the Millbrae station and BART, so Fresno-SFO local air substitution should be possible. I've said before that, if operated properly, HSR could eat United Express' lunch on that run. Bakersfield-LAX is another story, since there seemingly was never any thought of extending actual HSR service to LAX. BUR service is fine, but that's a small, secondary airport that only provides limited domestic air service. Lack of LAX access is a serious failing for HSR, though it's understandable due to the downtown-downtown tunnel vision of the supporters, and due to the undeniably high cost of building anything between downtown and the airport. Still, the SFO connection is maybe a 15 minute trip including a reasonable wait for a BART shuttle (if BART would run one). LAUS to LAX is at least an hour, even using a taxi or Uber, other than possibly in the wee hours. Not practical.