This is a problem in much the same vein as the aforementioned issue of player interaction during public events, but on such a much larger scale due to its sheer necessity. Not being able to adequately communicate with random players is one thing; not being able to access content is another entirely. In direct opposition to its multiplayer backbone, much of Destiny's cooperative content is off-limits to players without a Fireteam of friends to regularly play with. The absence of matchmaking - a queue to form Raid groups from players in waiting - severely hinders the accessibility of end-game content. Short of personally messaging everyone you happen upon or scouring forums, there's no way to form a proper Raid group; and those are ineffectual even at peak hours. Besides, if there's one thing Destiny's laughable story delivery has proven, it's that if content isn't available in-game and must instead be sought out separately, it doesn't matter to the players.
A freelance games writer, you say? Typically battling his current RPG addiction and ceaseless perfectionism? A fan of horror but too big a sissy to play for more than a couple of hours? Spends far too much time on JRPGs and gets way too angry with card games?
Well that doesn't sound anything like me.