They're addressing some of this with TTK. At least, if some of their interviews are to be believed. Some strikes are getting remixed versions and they've gone on record in saying that they're becoming more comfortable with letting people do endgame activities with randoms since it's seemed to have worked out. The LFG threads and existence of sites like that have pointed to the fact that they're trying to find ways to address matchmaking problems while still keeping some of the content exclusive to dedicated parties. Granted, that doesn't point to matchmaking finding it's way to VoG or Crota, but they're going to figure out something for it at some point. You have to realize, this content wasn't originally intended to be beaten into the ground the way it has been by the community. Vault of Glass made sense at the time to be taken out by a dedicated group because of how epic the encounter was. Based on the interest though in these types of activities and the speed at which the community has consumed it, Bungie is basically retrofitting the existing game to be bigger and have more depth in these big moments. They're turning an 80+ hour game into something the community has basically made into something that can last 500+ hours. It's going to take time, especially with how the existing design works and how old platforms are restricting certain features.