The problem is that same person can pay about $50 for gas to go from SF to LA and have the car with them in LA or pay $130 for a one way ticket (I haven't read the numbers but that's about the cost in Japan and I expect other countries with high speed rail). Then you have to get to the station which might be a little far for some.

I really love the high speed rail system in Japan and Europe but it's not cheap.

Those prices for car are heavily subsidized and don't account for all costs. Gas, highways, cost of car and maintnence....

If you look at HsR in Europe and Japan, you notice that driving isn't heavily subsidized so it wins in a clear way.