Little skill required to to get light levels. Only time and luck required. Bad player is bad player regardless of light level. I've ran hard mode at under 310 light. It a good deal harder but still possible so long as everyone works well as a team. This raid is largely about coordination over raw skill or gear. But yeah there is a such thing as too low a lvl for a raid. It's based on individual skill. That particular player was too low of level for hard raid given his skill.