That's a single 35 mile tunnel, in a comparably geographically stable area. The high speed rail project would need essentially two of those, each of which would need to cross the San Andreas fault. Additionally, a substantial amount of the remaining amount of track would need to be newly laid, because the existing rail infrastructure in the area is already near capacity, and the freight companies are hostile to any sort of improvements to passenger infrastructure. Yes, some of the issue is political, but it is an immensely challenging engineering problem to work through.