Well, no. It rarely did. Living or dying came down to the die roll, but heroism isn't measured by that. Heroism is measured by the RISK of death, not the act of living or dying to the die roll.
In real life, it's heroic for someone to run into a burning building to rescue someone. He risks being killed by fire, smoke or weakened portions of the building. He may never actually get burned, come close being overcome by the smoke, or encounter a weak part of the house. It's the risk he's taking that determines the heroism. D&D is like that. The PC may never even have to make that roll, but if he's risking death, he can be heroic. If the risk of death is lowered or virtually removed, so too is the heroism.