OAK
Oaktree Capital Group LLC
stock NYSE

I would pick the plane.
I live in south Orange County CA. For work, there is ample reason to make trips to and from San Jose.
Seems like an easy win for HSR, right? The proposed LA-SF HSR line is supposed to make a stop in San Jose!
But... The devil's in the details. For me to take the Los Angeles -> San Jose route I'd need to start by hopping on a train in Irvine, to Los Angeles. It'll take me 10 minutes to drive to the Irvine station and I need to get there at least 10-15 minutes before the train leaves, so that's \~25 minutes. Irvine->LA is another \~50 minutes. From there I need to build in enough time to catch my train at Union Station. So build in another 20-30 minutes to deal with delays. The Los Angeles to San Francisco route, I've heard best case is a little under 3 hours. Let's just assume it's 2:15 from Los Angeles to San Jose which is an earlier stop. Now I need a rental car or an Uber, which I'll need whether it's air travel or HSR, so we'll assume that's a 15-20 minute process either way. So all in, I'm looking at a little over 4 hours, best case.
Compare that to flying. It takes me about 30 minutes to drive to SNA and park. SNA is a quick airport, so I don't need to get there less than about 1:15 before my flight time including TSA (Precheck for me); I can cut it closer but rarely do. The flight is an hour. (I carry on so there's no baggage claim.) Add 20 minutes for Uber/rental. I'm maybe a little over 3 hours total.
Generally from what I see, the HSR ticket will be equally expensive to flying, but slower and more of a hassle. Flying gives me the opportunity when I need to, to make same-day trips to and from the Bay Area. Leave in the morning, come back in the evening. Adding an hour+ to each direction of the trip makes that a little more difficult.
HSR works if it leaves EXACTLY where you live and arrives EXACTLY where you want to be. But that's not all that common. Here in SoCal, we have 5 major airports (LAX/Burbank/LB/SNA/ONT). The Bay Area has 3 (SFO/SJC/OAK). And there are PLENTY of flights every day between all of them, far more flights than how many trains will run IMHO. Which means it's often easier to get to an airport in either region than it is to get to the HSR hubs, and the massive number of flights give more optionality on schedule. As mentioned, for me to get to the HSR hub (Union Station) I need to hop another train from Irvine to be there, adding an hour of transit time--basically the same amount of time my plane would be in the air, JUST to get to the HSR terminus.
So yes, I would choose the plane.

I would pick the plane.
I live in south Orange County CA. For work, there is ample reason to make trips to and from San Jose.
Seems like an easy win for HSR, right? The proposed LA-SF HSR line is supposed to make a stop in San Jose!
But... The devil's in the details. For me to take the Los Angeles -> San Jose route I'd need to start by hopping on a train in Irvine, to Los Angeles. It'll take me 10 minutes to drive to the Irvine station and I need to get there at least 10-15 minutes before the train leaves, so that's \~25 minutes. Irvine->LA is another \~50 minutes. From there I need to build in enough time to catch my train at Union Station. So build in another 20-30 minutes to deal with delays. The Los Angeles to San Francisco route, I've heard best case is a little under 3 hours. Let's just assume it's 2:15 from Los Angeles to San Jose which is an earlier stop. Now I need a rental car or an Uber, which I'll need whether it's air travel or HSR, so we'll assume that's a 15-20 minute process either way. So all in, I'm looking at a little over 4 hours, best case.
Compare that to flying. It takes me about 30 minutes to drive to SNA and park. SNA is a quick airport, so I don't need to get there less than about 1:15 before my flight time including TSA (Precheck for me); I can cut it closer but rarely do. The flight is an hour. (I carry on so there's no baggage claim.) Add 20 minutes for Uber/rental. I'm maybe a little over 3 hours total.
Generally from what I see, the HSR ticket will be equally expensive to flying, but slower and more of a hassle. Flying gives me the opportunity when I need to, to make same-day trips to and from the Bay Area. Leave in the morning, come back in the evening. Adding an hour+ to each direction of the trip makes that a little more difficult.
HSR works if it leaves EXACTLY where you live and arrives EXACTLY where you want to be. But that's not all that common. Here in SoCal, we have 5 major airports (LAX/Burbank/LB/SNA/ONT). The Bay Area has 3 (SFO/SJC/OAK). And there are PLENTY of flights every day between all of them, far more flights than how many trains will run IMHO. Which means it's often easier to get to an airport in either region than it is to get to the HSR hubs, and the massive number of flights give more optionality on schedule. As mentioned, for me to get to the HSR hub (Union Station) I need to hop another train from Irvine to be there, adding an hour of transit time--basically the same amount of time my plane would be in the air, JUST to get to the HSR terminus.
So yes, I would choose the plane.