Most of the playerbase of this game is actually really, really bad. You only need to take a sniff at Crucible to see this. It's the same for any game with a mixture difficulties of content. This is not a surprise. I can almost guarantee that if this raid had matchmaking, you'd have around the same number of Oryx kills. Or hell, even less. Sure, participation numbers would be immensely higher. But how many of those random-matchmade groups with no communication, no co-ordination, and no way to remove troublesome (or even AFK) elements would make it all the way? They wouldn't even get past Warpriest.