As long as vision zero is considered more of a gross infringement on personal freedums than a laudable goal, making trains as safe as they are uniquely fit to become is not exactly a great way to allocate funds to maximize impact. Trains are already very safe. Even where they currently lack 4 layers of fail-safe systems operated at a level where that still permits reliable&punctual service. The same money on making them shine could be spent on improving car infrastructure (or even removing some car infrastructure!) for greater expected harm reduction.