Yeah the point of them is that they're ultimately grey. They're blocked from doing the most good and to a reasonable degree from doing the most evil. But they're self destructive no matter what and for every group of heroes you get from them, you get similar groups of villains. They're knights in shining armor, some gallant and heroic and others self interested bullies, trying to keep everyone else from returning to an advanced society, but also trying to protect them from the evils of it.

The biggest thing is they can't maintain any moral character from group to group or generation to generation. They're too insulated, too ideologically bound (in a way completely separated from morality), too focused on their goals. They hate the Enclave, sure, but in part because both see themselves as what's left of the government, they hate Caesar, but they also hate other grey factions like the NCR and the institute, and they can't see the good of the railroad.