While this article finds an issue with the way the Tejon Pass route was eliminated in favor of the Tehachapi Pass route, Tejon Pass route would skip a station in Lancaster/Palmdale, which would be a mistake. As the article acknowledges, these are rapidly growing exurbs that are refuge from the exorbitant land prices in the LA Basin. There is existing commuter rail service between there and Downtown LA, but a HSR is a significant level-of-service upgrade, and offers connections to Bakersfield and beyond. The fact that a rail line offers connections between many points with the same service, while air service must fly at least as many services as there are destinations, is lost on these commentators.
That being said, there are many facepalm-worthy decisions made by CAHSR or by others early on in the process, like an extremely sweeping curve on a long, expensive viaduct just outside of Fresno station [1], or the barely-realistic journey times written into legislation that drive up cost. Another is the choice of the torturous Pacheco Pass over the easier Altamont, or even going around the mountains following the Strait the old rail does. Besides, there's no point to pining after LA-SF rail traffic when airports are perfectly fine between those two. But what about LA-Bakersfield? Modesto-Sacramento? SF-Fresno? That's where a train helps. And to do that, all you need is a train that does comfy, European speeds like 100 mph, instead of a painstakingly-built one that does twice as fast.
[1] https://news.ycombinator.com/item?id=16172313