It's very sad, especially for relatives of the dead man, just the same as when someone gets killed in a road traffic accident.
The fact remains though, that when a train weighing several hundred tonnes is belting along at 100mph or more it isn't exactly being stealthy. All anyone has to do is LOOK. You can see for hundreds of yards in either direction. Trains are BIG, something like 9ft wide and 12 tall, they make a lot of noise, the ground shakes, the rails sing. People who step out in front of trains are, by and large, not paying attention.